+logan buck if only other people realized the same works for dogs, so they dont need to freak out when they see dogs out in someones yard on a winter day. Many dogs (especially ones with thicker fur) prefer to be outside to cool off.
And polar bears are painted black, so they absorb more of the sun light - the fur is actually channeling the light onto the skin. Polar bears are so cool on many levels!
Great video man. Very enjoyable. And I think we almost came to the same conclusion, that with airflow there was a negligible difference. But with no airflow, we saw, and measured a significant difference. We stand by the results we achieved on the day, though we can't be sure how the results will apply to each persons circumstance. One important point and comment is that you stated that car manufacturers don't make black radiators and went on to say "Does this mean major car manufacturers don't understand emissivety?" But a huge amount of cars do have black radiators. It would be interesting to know why? We're really glad our original video has inspired a lot of debate, conversation and education - it's exactly why we do these kinds of videos. You should jump onto the MCM forum and add to the discussion. There's a 10 page thread on this topic already. Hopefully we'll see you there! Cheers!
Mighty Car Mods I was hoping you guys would show up! :D I was thinking throughout the whole video about how he doesn't mention the advantage in no airflow. For me, a commute with stop-and-go traffic, I see an advantage, and will be painting it black on my Subaru when I get the time to dismantle the thing.
Lol you stand by the results I just lost a whole lot of respect for mcm he explained radiation and convection theres no point in having a cooler intercooler if you not on boost/ not moving
Jeremy quiring It's not all about power, turbocharged cars are very fuel efficient. A smaller motor can make the power of a big motor, but only when needed. Sitting at idle or low speed with a lower intake temp is a benefit for my fuel economy, as my engine can use even less fuel to maintain enough power to idle. Also, in a drag race, staging (vrooom popopopopopop) a turbo car can see benefits on the line from a cooler intake temp. Just depends, clearly there are advantages and disadvantages to this mod. Decide for yourself what your car might need.
I respect both youtube channel but I don't know who to trust. Mighty Car Mods need to DYNO the Sliver and Black Intercooler to back up their claims with more empirical evidence.
Best finish would be clean/polished aluminum. Next best finish (it won't look corroded in a few months or corrode and crack/fail in areas where water/dirt/salt can collect in the fins) would be anodized aluminum as while anodizing is also insulating, it is far far thinner than any kind of paint (and also lighter BTW). It is also very hard and abrasion resistant. Read up at en.wikipedia.org/wiki/Anodizing under 'Sulfuric acid anodizing (Type II & III)' 'Type II Coatings of moderate thickness 1.8 μm to 25 μm (0.00007" to 0.001") are known as Type II in North America, as named by MIL-A-8625'. Yep - as thin as 7 one hundreds of 1 thousands of an inch (or 7% of 0.001" - difficult to measure) up to one thousands of an inch of an aluminum oxide layer that can be uniformly and consistently be coloured (BLACK? or a hundred other colours - RED perhaps?, or just natural aluminum - the colouring won't effect final coating properties except for the MAAAD results) in the anodizing process (colouring won't change the thermal conductivity). I've had a few VW (1983 to 1997) and the aluminum rad cores have NEVER failed. The joint between the AL rad core and the thermoplastic end caps has always been the point of failure. Problems - anodizing is a thermal and an electrical insulation so modifications (welding on/fixing brackets) requires a bit of grinding/sanding to remove the anodizing in that location (same as you'd remove paint in that area) which ruins the anodizing in that area. Aluminum pop/beer cans have a total PAINT thickness (inside and out) of about one thousandths of an inch (25 μm - pretty good and uniform but not abrasion, corrosion weather resistant). Anyone with any kind of spray on paint will NEVER be able to provide a consistent thickness of paint over the huge area of the inter-cooler 'tubes' and paper thin fins as it is nearly impossible to paint the deep recesses created. Paint sticks much better to an anodized AL surface than a bare aluminum surface unless using a specific bare AL primer (ANOTHER layer of paint - the primer - is counterproductive for heat transfer). Absolute best - car that never sees anything other than the track or lives in a desert - BARE ALUMINUM. Next - Anodizing AFTER all bracket modifications, etc have been performed. Next - anodize all over, tape off the inner part of the inter-cooler (inner tubes and fins) and spray paint the OUTER surfaces of the inter-cooler.
As an engineer you have no idea how good to hear someone 1) Make sense 2) Explain and recherche and back up his idea with ACTUAL real knowledge.... 3) I love that book!!! 4) Thermo at work!!!
As a very well read ex-physics student gone machinist, I would like to add 2 very important points to Engineering Explained's video. Normal black paint has a high emissivity in the VISIBLE spectrum. A car intercooler never gets hot enough to emit radiation in the visible spectrum! It is highly unlikely that whatever black paint is being used is 'black in the infrared' too - the intercooler will only emit radiation in the infrared, hence the idea of using black paint is a moot point from the beginning. You would want a coating that has an absorption spectrum from 700nm to 1mm lambda. Point 2 is something you never went over, and that is why their intercool was more efficient without airflow with black paint than without paint. The answer is simple: The solvent in the paint must vaporize/flash off in order to dry. When this is happening, there is a phase transition from liquid to gas, which absorbs heat from the immediate substrate (the intercooler) in order to accomplish the phase transition. THIS is why the intercooler was cooling so much better at first with the black paint and no air flow! The paint drying was sucking the heat off of it!
+DjRjSolarStar Indeed, the only way they could have been so wrong in their results is if they ran their 2nd 'test' before the paint was completely dry. Evaporative cooling FTW. Moral of the story: Mechatronics engineer should stick to mechatronics.
If you were a teacher in my science class, when I was in school, I would've enjoyed it a lot more. You're awesome at giving information in a way that it's fun to pay attention and learn. Thank you for doing what you do
I'm not a mechanical engineer and I thought painting the intercooler black was obviously going to yield worse performance. Good video though - I wasn't expecting to learn as much as I did, and you did a great job at proving someone wrong while being perfectly humble about it.
Blows me away that anyone would think that painting something black would help cooling. If you want a better intercooler put away the rattle-cans and go air-to-water. I thought the original idea behind painting intercoolers black was to help hide them in sleepers.
Actually most Montune and Cobb intercoolers come with some portion of black, Montune is completely black. These companies actually employ ME's with automotive backgrounds. This is just like buying a shirt in the hot summer, you can go with the white Hanes tee-shirt or a identical tee-shirt made the exact same but is dark blue with the Hoonigan slogan on the the front. You will pay more money for darker Hoonigan shirt, since it's the same shirt you are paying for a logo and the Suns heat will heat up the more expensive shirt. It is all in branding and what people think is cool. Intercoolers are ultimately made of raw aluminum, but can sell an inexperienced modifier a black one for an extra 50$, or whatever.
The Focus RS also includes a plate to make the intercooler even less efficient than just painting it black. Therefore all intercoolers should have blocking plates? Being an owner of the Focus RS, I'm here to tell you, this car is not made for track driving at all.
OK, after watching the MCM video I think I figured out why they got such an improvement from painting the intercooler (during the no fan test). It's because the the intercooler is covered in fresh paint. (they even made a point of putting a ton of paint on the thing) And that paint is still evaporating it's solvents. So it is not just giving off heat by radiation. It is also evaporating, and of course there is some airflow due to convection. Given enough time to cure, a week a month... the advantage of the fresh paint will disappear. And the 3% gap seen with airflow will widen. Oh, and of course, painting the intercooler black does not eliminate the original surface of the intercooler. It's still there, and must now transmit it's heat to the paint.
I can say with first hand experience that major automotive manufacturers do in fact paint intercoolers, radiators, and condensers black. Its 100% for looks. You are correct that this does slightly diminish the returns of the heat exchanger, the parts are generally designed with this in mind. Also, when paint is applied, its done in a very thin layer to reduce the loss in efficiency, and to not coat the inner portions of the fins or tubes where most of the surface area is. So yes your right that its better to leave the metal bare, but the losses shouldn't be significant due to a light coat of paint. Source: I work for a major OEM parts manufacturer where these components are made and some are painted black as well.
I just got finished testing both of my intercoolers (Twin Turbo side mounts) I left one as is and I coated one with thermal dispersant paint. To those that argue that coating the IC will create a thermal insulator, consider the material you are using...if the coating has a specific heat capacity that is better than the substrate, you will conduct in the direction of the coating. If it is worse than the substrate, you will insulate that substrate. I ran a test similar to mighty car mods but with better controls. Instead of running an ambient fan I built a shroud to activate the intercooler cooling surface (this is equivalent to the car moving). Might Car Mods is hyper-focused on emissivity when there are other factors that cause the improvement in IC efficiency. Without Coating, We heated the intercooler body to 185F. The Instantaneous Peak IC Inlet Temp vs Output temp was 82 Deg F. With Coating, the Delta at the same IC heat soak peak temp was 135 Deg F. This is almost a 40% reduction in temperature! The coating is designed to increase conduction and convection of heat and this simulation depicts conditions of what happens in intercoolers after an increase in turbo boost. The result is that the coating gives one's vehicle a better margin of safety against potential pre-ignition/detonation due to high engine inlet temps. This also means you can run higher boost pressures for better performance. The test setup had thermocouples in ambiet air 5 feet away from the test rig and an additional TC in the fan shroud 5 inches from the IC's cooling fins(inside of the fan shroud). The other 3 were at the IC's inlet, Halfway through the IC cooling fin body (inside of the fins) and the last one at the outlet. All equipment was Calibrated. Equipment used: Degree ATM 2400 and USB UTS100T thermocouples.
Great video. I just put a fat Turbo on my Polaris RZR 900 and everyone and their brother says i should paint it black (my intercooler). F that...the first thing i thought to myself was that the paint will act as an insulator and on top of that, mine is in direct sunlight so it would also absorb heat as well. I am not an engineer so if someone like me can figure out that basic common sense, i wonder why others seem to think different? The mighty car mods thing is good to i agree because they are awesome but your's is a more logical explanation of what is happening. Oh, and you just earned yourself another subscriber - thanks!
Engineering Explained haha, right on man, good to hear that!!! I appreciate it man and now that i found you ill be watching quite a few of your's! Love your channel!
"I am not an engineer so if someone like me can figure out that basic common sense, i wonder why others seem to think different?" I am an engineer, and the answer is: Application. For engines that make boost at low rpm, like superchargers or even many modern turbos, the 60% increase in heat transfer at these low rpm and low vehicle speeds can be a boon for the 0-60 and 1/4 mile times. That 3% loss would be an issue on the circuit, however, as the vehicle relies on mid and top-end power.
Engineering Explained i actually ended up painting my intercooler....but not to gain any heat dissipation which i know won't happen. I did it for looks. Even though i am sure some of the paint got inside the fins, we specifically didn't soak the crap out of it and focused on just the outside area so i could get a logo stenciled in. If you look close at it you can see the aluminum inside the core still. So I know i said i wouldn't do it but i mainly did it knowing it probably won't help but also that it really shouldn't hurt much either. I stuck 2 giant fans on the intercooler as well where i never had them before so it should be good to go i think.
When I finished watching their video a few weeks ago the first thing I wondered was what you'd have to say about their conclusion. You are like a younger Bill Nye. It's one thing to know your stuff but the real talent is making it understandable to non engineers & you sir are awesome at it. I've subscribed for years & keep coming back for more.
Thanks! Bill Nye has always been an inspiration. Like the master himself, I only have a bachelors of science in mechanical engineering. An interesting fact on the guy. I appreciate your viewership!
Colin Griffin well technically, the sun is out even at night. Unless it's a full moon (or new moon? Can't remember which one is pitch black lol) as the moon light is simply just a reflection of the sun's light lol. Same way as you would say "he pointed a laser at my eyes" even if it wasn't laser to person, but rather laser to mirror to person.
Nor Dic 89-03 (1st and 2nd gen 12v Cummins add 2nd gen 24v) are aluminum supplyed to dodge painted black... I have a 91.5 that is tore down to receive an 03 IC both stock black. I guess this makes Cummins/ Dodge a minor OEM ... I'm in agreeance shame on them for having painted these black.
As a fellow engineer I have to say that I absolutely love your videos, you're one of the few YT sources that actually has knowledge of the engineering, physical phenomena and practical knowledge of cars. I salute you! :D
Radiators in cars used to be black when they were made of copper. Now they are aluminium they are silvery. Probably because copper needed painting to stop it corroding. The aluminium is protected from corroding by an oxide layer that is increased in thickness by anodising, it would be easy to anodise them black, without any insulating effect if it made a ha'porth of difference. Which it doesn't, so they don't.
Redd's laws of thermodynamics: 1) You can't win (you can't get more energy out of a system than you put in, conservation of energy) 2) You can't break even (Friction, loss, etc. you will always have less energy out than is put into a system, entropic principal) 3) You can't leave the game (Unless we find another universe with completely different rules, and even then it's not very likely that you could circumvent rules 1 and 2 in any universe conceivable that contains matter)
Your statements are very true and very misleading (not true) at the same time: - "you can't get more energy out of a system, than you put in" - complete nonsense, we both know that, right? I can trigger a process, using a small amount of energy, for a much larger energy transfer from the environment. Just like a heat pump does. Or a transistor. Or an implosion atomic bomb. The true statement would be "you can't get more energy out of a system, than WHAT'S ALREADY IN IT". Doesn't matter how much you are putting in. The environment could be putting in a LOT more, than you are. - "you will always have less energy out than is put into a system" - Exactly correct. Notice, how this statement contradicts the very first one directly. In majority of cases, there is an additional energy being delivered from the environment anyway, in the form of heat (infrared), microwaves, x-rays, etc. - "you can't leave the game"... What game?
@TheRadiastral The energy is already there for those things, you're forgetting that you also put the materials (therefore the mass/atomic bonds) into the system.
I already feel smarter and I like the way you set out your vids and how you explain everything on the board. I also think it will be really cool to see you modifying the integra but with your added knowledge and take on things. Good luck with furure vids!
Black intercoolers on many 80s and 90s JDM cars - Impreza, Legacy, Skyline, Supra, plenty more. The Lancia Delta HF Integrale too. After the 90s, I can't think of any. Did they get smart or are they doing it for good looks? I don't know. Though this does bring to mind drilled rotors on new cars.
Well i think stationary performance is often called "swag" or more accurately "looking cool". As the word "cool" suggests, cars with higher stationary performance run cooler all around. Sounds completely logical right?
+Engineering Explained Great video. I understand the Intercoolers & Radiators function - BUT why not have a intertwined radiator built into the intercooler? One water channel, one air channel and so on... OR will the hot turbo air heat the water and thus cause the air to remain hot?
Cengal & Boles- same thermo book I used at University of Portland nearly 20 years ago. Very well done (especially compared to my confusing Shigley machine design book). I remember one of the problems in the book was calculating black vs. chrome cooling fins on an air-cooled motorcycle engine like a Harley (no cooling fan). At speed, convection overwhelmed radiation and made it negligible, but at idle where you have only natural convection, there was a small but significantly useful advantage to the black fins...something like 10% or less. A 10% advantage is important if you're about to overheat in traffic. They probably would've been closer to 10% without the insulating layer of paint. A black intercooler might slightly help your intercooler while you're stopped, particularly if you anodize it instead of painting it, but it won't make a difference once you're moving so probably isn't worth the effort. Also, it's been a while, but shouldn't you have used absolute temperature?
To be honest, I think the biggest issue that needs to be discussed in this is ducting and not the painting. 90% of the time I would say lack of proper ducting far greater outweighs the 3% difference in temperature. I can't even count how many intercoolers that mostly are just stuck in the front of the car and not properly ducted. And that ducting is to be applied on both sides ( air being rammed through the front of the car at speeds, as well as the fan being properly ducted to pull at idle properly.) I haven't done any testing properly, but I think that should be done in 3 tests though, one with just a fan stuck on there, second one with a fan with a fan shroud bolted on, and thirdly with the fan and shroud sealed with tape or foam tape to ensure all corners are properly air sealed. Lastly before getting back into painted vs non painted, another big factor that I often see is lots of fins being bent. Even a slight bend can reduce the flow pretty drastically. Its not uncommon for me to see radiators and intercoolers with probably about 10% of the fins bent in ( or actually on the topic of fins, being filled with bugs or dirt and grime) that would far out weight the paint discussion. Now to get to the heart of the the topic, I do have some issues with "jumping to conclusion " that a painted intercooler, vs a non painted one actually makes a difference. There are lots of open loops here, one there's a big difference in entirely painted (think of it dipped into a paint tank and then pulled out) the other part could be just lightly painted to change the frontal color ( keep in mind , probably over 99% of the non painted surfaces are still bare aluminium. ) One major factor plays here in regards of that and that is core thickness. The thicker the core, the less the percentage of the painted area is in the case of spray painting the front faces to non painted is). Another angle to consider is age. As the cores age, oxidisation occurs on the bare aluminium. Does this oxidisation layer make the core less or still "more" effective than a painted one that may have oxidised less over the year due to the protection provided by the paint. ... In summary, painted or not, that is the least of any of the major issues to be concerned about in regards of a cooling effect of radiator or intercooler.
lol once I saw the title of this video, I can Imagine Engineering Explained watching the MCM video and thinking: "Fuck... I don't want to have to do this... Seriously? Looks like I'm going to have to bring out the whiteboard"
I worked manufacturing high end radiators and intercoolers for mining equipment (mainly). ALL were painted black before being bolted together with the condenser (and sometimes even fuel coolers, often only seen on the really big rigs used to do outback trucking).
Imagine that 3% at 70mph on the highway! Just a tiny fan produced a temperature difference of 3 degrees C. I would imagine that the amount of air flowing through an intercooler on a drag strip going 90mph would be significantly higher and that 3 degrees would be multiplied tenfold.
Engineering Explained Now imagine if the intercooler was 30 degrees cooler before it had 90 mph winds blowing through it on the drag strip, you know, because of less heat soak from idling in the staging lanes for 20 minutes... If the MCM data is correct, then the intercooler will be 30 degrees cooler at the starting line. The air going through the intercooler isn't going to cool it 30 degrees in 10-15 seconds the car is moving down the strip, especially since the car will be at full boost the whole pass. Not saying your video is wrong, I just want you to mythbust the advantages of a black intercooler reducing heat soak.
cody clark Well, if you think about it this way; If black radiates but also absorbs heat more easily, the intercooler may well heat soak faster if it is in the engine bay near to things that radiate a lot of heat. Furthermore, if the air temperature around is hotter than or close to the temperature of the air flowing through it (in the case of the air intake location being cooler air, or air at the same temperature as the intercooler's location), the intercooler will probably not cool the air very much through radiation because it's close to being in equilibrium, the heat wants to flow from an area of high concentration to an area of lower concentration. In the MCM video the heat soaked intercooler was on a table at room temperature which is basically best-case scenario for allowing the heat to radiate, in a real car the situation is not likely that ideal, being close to hot blacktop and possibly an exhaust manifold. If, for example, you had a black and a raw aluminum intercooler in the same place on identical cars lined up at the strip (for worse case scenario, think subaru top-mount, or a front mount on a honda that sits very very close to the exhaust manifold and very close to a hot road surface, where the radiant heat will be at it's worst) you would expect the aluminum intercooler to heat soak more slowly because the radiant outside of the intercooler is greater than inside. It would also cool down faster as the car pulled away down the strip. The only way it would be better would be if it was a very cold day, and mounted far away from anything under the hood that would radiate heat, and also not in direct sunlight. However, that improvement would come at the cost of making the car perform worse in hot conditions and in convection at speed. I think, anyway. It would be fun to test this with a car like the 300zx twin turbo because it has side mount intercoolers and the turbo system for each cylinder bank is a mirror image of the other, so you could paint one side and not the other.. and test the results.
I agree, but I would have argued with the mcm's results if I hadn't seen the video proving that the black intercooler actually lowered the boost air temps without air flow. I would like to see a test with the black intercooler with higher ambient temps to see if it really does help with heat soak.
I love this video! Seriously! Great video! "the more worthless the system is" LOL I love the side commentary. A little different take. My old competition drift car (pro am) I painted the back-side of the intercooler and radiator, but left the front side bare. Drift cars you RAIL on them, then you sit in staging and wait to get launched again; this is where we see immense heat soak issues arise. Logic behind painting back side, is the frontal (front half) of heat exchanger surface areas remain un-insulated, so where the temperature differential is the highest there is also minimal insulation. On the back side (also in the dark in the engine bay) it is black, this is where we want more radiative based cooling since we aren't moving, and everything is hot from a hard run, now bleeding heat into everything. We want the heat exchangers cool when we get launched so we don't feel a power loss, as this will change how you need to drive. New comp car, the heat exchangers are left polished for aesthetics, and water sprayers are installed, so when the car isn't moving we can spray water via button onto heat exchangers and allow evaporation to help disseminate thermal energy. (I'm assuming you like this method much more lol) Running Ethanol for fuel which burns colder also helps keeps temps lower. Effective ducting, and division of air channels so heat exchangers don't share air also helps. Anyway side tracked now.
Great video. You should be lecturing at Uni (if u aren't already). There is a real knack to being able to explain physics/engineering concepts- well teaching anything really,in general, and you have that knack.
Just wanted to point out that the mighty car mods test showed that the black radiator radiates heat better with no airflow but performs worse with airflow
I would say they're the hardest of the core mechanical engineering curriculum. The senior and upper division / elective engineering courses, which build off of the basic principles of thermo, heat transfer, and fluids are way harder.
EE - Going to mess with some of my mechanic friends. lol Check your personal Facebook (other messages) sent you a message about Engineering degrees etc. My initials are DH just in case you have quite a few messages.. Thank you. Awesome videos.
very informative info the one thing that i love in automotive engineering is usually the name of a part dictates it purpose/function amazing that it should actually be called a convection/er?
I enjoyed thermo too. As an engineer I sometimes forget what is such an obvious thing to me (from my education) and not to others. good video explaining. Its funny how often car trends are really bad for performance. Now I gotta go watch mighty car mods to see this.
There are aplenty of cars that come with black intercoolers. R32 - R34 GT-R, XR6 turbo comes with black intercooler just to name a few. For street applications, removing the black paint off a GT-R intercooler sees an INCREASE in average intake air temps. This is because there is no fan on the intercooler and only works when moving. On the street you are stopped a lot.
Engineering Explained Sir - Engineer to Engineer - Well explained :) I watched the MCM video and immediately went "meh". I thought it obvious that radiators are convective devices :) I'm thinking now about the R34 and the Ford Falcon XR6-Turbo. Okay - they are indeed black. But they also appear to be anodised. I'm assuming they do this to maintain a known condition of the metal - over time the metal would oxidize and become *slightly* less effective. So rather than a big, thick layer of paint - what about anodised aluminIum? Whilst it won't be as effective as bare metal, the process will keep that metal as effective for longer.
Another mechanical engineer here, here's my two cents. Painting an intercooler in the hope of performance gains is misguided, and that's well explained in the video. One thing that wasn't totally covered is just how insignificant radiation is in a system like this (VERY). But it's a good video. However a lot of people are looking for the aesthetic effect, since an unpainted aluminium fmic is not to everyone's taste. If you paint the front surface only, so that only the leading edges of the fins are painted, you will get virtually the same aesthetic effect and it will have minimal effect on heat transfer, since most of the surface area of the fins will remain unmodified (all the heat transfer work is done on the surfaces parallel with the airflow, the parts of the fins you can't really see, which have enormous surface area). You would be painting a fraction of a percent of the surface area. Obviously it would have to be done by hand as opposed to spraying. Personally I would leave the intercooler alone and go with a dark grille in the bumper in front of it. It will tone down the look of the car and protect the fragile fins from being damaged by road debris. Over time you get enough dents and that will drop the efficiency of the heat exchanger substantially, as the airflow between the fins gets blocked/disrupted. So add a grille, it's functional and you can adjust aesthetics with it without goofing around with important engine parts.
+Faketrollname sevenbillion Kind of a random question here from an engineering student, but one thing I've always wondered is why they don't use the hood for cooling? Construct it from aluminum and put fins on it like a heatsink. Wouldn't that eliminate the need for airflow through the engine bay, and reduce some drag?
decidiousrex Because you couldn't transfer enough heat fast enough from the block, through the air, into the hood. If you decided to use a coolant fluid to get the heat up there, it would be more complication than it was worth, as the system would need to detach when the hood was opened, and finding a location for the expansion tank would be hard. If you did figure out some way to get the heat up into the hood that was simpler than a normal system, you would then have to figure out what to do when the car was static (natural convection isn't enough), which would mean a fan drawing air over the hood, and I'm not sure how you'd package that. The fins on the hood would make engineering for pedestrian safety more complicated. I'm not saying it's impossible, but those are a few drawbacks I can think of.
Faketrollname sevenbillion Definitely some obstacles I didn't think of. That's more of an idea I thought of while in the shower than a seriously thought out plan. I'm sure if the saving in drag (if there is any) outweighed the added complication, automakers would be using that system. I'd rather see thermoelectric power generation used to cool cars, unfortunately the tech simply isn't there right now. Maybe someday....
+decidiousrex I had a coleg how said that there are sport motorcycles that use the body of the bike as a radiator with integrated pipes but is very expensive to repair if damaged. I am not sure if is true, not sure if I remember corectly.
+Adrian Draganescu , this is true of the Harley V-ROD. Only that the oil from the engine and water is going through part of the cycle FRAME like a water jacket. I added an optional oil cooler ( like a black small intercooler ) to dissipate heat while on the road between Houston , Tx and Arizona. It helps drop the temp in the engine by at least 10 degrees. It comes anodized black just to match the bike. JK.
I don't get it? Looking at the formula, 1.03 is the Q for no2, not no1. Surely the rate of heat transfer is higher for the black intercooler as it has rejected more heat to atmosphere than the silver one with all other things being equal. An IAT of 97 is better than 100, so it's more efficient. Please can someone explain why I'm wrong? Cheers, Tom
Excellent video although I don't know anywhere on earth you can have a hot sunny night. You can have sunny night near the poles (if you base night on time of day) but I wouldn't exactly call it hot.
That MCM video also made me cringe a bit. What they seemed to fail to realize is that an intercooler is mainly used to cool air that was heated by using forced induction (turbo, supercharger). When your car is standing still, you have no boost, and no need of it, so there is also no super hot air to cool.
Just a thought on the "3%" difference. Shouldn't you be using Kelvin, not Celsius? I'm not sure if anyone has pointed this out yet but really the difference would be 373/370 (1.008, so 0.8%) not 100/97 (1.031, or 3.1%)
But if the result is in Kelvin then to have it as a percentage of the original temperature, the original temp. has to be in the same units. Otherwise it's like saying 50 miles is half of 100km
Adam Hansen in this case it's the change in temperature that matters not the temperature itself, a change of 97C would be the same as a 97K chane where as a room at 97C is equivalent to a room at 370K. basically these two temperatures changes in kelvin would be 97K and 100K = the same thing
mastafixa I understand that Kelvin and Celsius use the same increments, but Kelvin starts at 0 whereas Celsius starts at -273. My point is that in SI units, Kelvin is used not Celsius or Fahrenheit. Mauswerkz said this in the MCM video - Around about the 8:30 mark "That doesn't necessarily mean it's doubled it's efficiency though?" "No, it's not twice as efficient just because you've seen double the difference; it doesn't work that way with Celsius." Temperature is a measurement of vibrations in molecules (as I understand it) so higher temperatures = more vibrations and lower temperatures = less vibrations right the way down to absolute zero where the vibrations stop altogether, which is at 0K or -273.15°C The vibrations CAN'T reach a negative amount so in this application, to calculate the percentage difference between the two results you have to use a scale that starts at zero, so you must use Kelvin. The difference between 97K and 100K as a % difference is NOT the same as 97°C vs 100°C. I know the difference is 3K or 3°C because they use the same increments but percentage wise they are very different scales.
Just helped two people decide to purchase a silver intercooler over a black one for our VW GTIs, by showing them this video. Great job again sir! Extremely useful info
***** You are right. I would prefer 100 degrees. Thus the SILVER intercooler. Thus they are not right in stating that the black intercooler is better and their own numbers show that. ("They" and "their" are Mighty car mods of course. I guess we got confused because my comment was a response to someone saying "but might car mod proved it", which was later deleted.)
I know this is an older video, but I was wondering if you know why almost all radiators for warercooled pc's (which use fans to cool them) are black? Would this be purely aesthetic, or do you know if there are examples of paint which interfere so little with the air flow that the emissivity of the black paint and the heat lost through this could positively effect rate of heat transfer. i.e a paint so thin that the pros outweigh the cons...
billy653 I can probably answer this. It's the same reason almost all radiators in older cars are painted black. Copper. Copper has been the material of choice for radiators for a long time, but the issue with copper is it readily oxidizes. So manufacturers coat them in black paint to protect the copper for the atmosphere.
+Pony Power That's far too fast to jump to a conclusion there. It strongly depends on the manufacturer of the radiators. For example Alphacool is always using copper for their radiators with a really thin black layer on the outside, but NOT on the fins of the rad. (See topic of insulating layers) So just saying they paint it for hiding bad quality is bullshit and probably only counts for cheap rads where common sense already tells me that a cheap rad will be manufactured cheaply. Also, Alphacool already sells white radiators. The colour design of those radiators have to match as many PC-builds as possible, else they wouldn't sell enough units and the most neutral colour that in 99 % of the cases fits to any colour-scheme, is black.
+MadJEFF I'm not a scientist, but I'm pretty sure most formulas are designed to work with degrees K, because the Celsius scale doesn't exactly correspond with the energy of a system. For example, because the Celsius scale can be negative, a body at 25 C actually contains about 92.2% of the energy of a similar body at 50 C. With Kelvin, because the scale bottoms out at 0, a body at 25 K contains 50% of the heat energy of a body at 50 K. This makes the math a lot easier.
+pokk700 That triangle symbol by the temperature, delta, means difference. We're talking about differences here, not absolute magnitudes. And a difference of 10 degrees K (or C, same thing) is the same no matter where you place 0.
even after 4 years I find this video is still one of my favorites. I even linked it to a thread wherein a vendor was answering me as to why the intercooler (being offered for sale) was painted black: "purely for looks" was the reply. That's when I posted the link to this video. I suppose marketing trumped science in that decision-making exercise. Always good to learn from someone who brings science to the discussion.
Brilliant, brilliant BRILLIANT The number of stand up aguements I've had with people who swear you should paint them black! the trouble is people are mixing up and confusing radiation and convection. After all, your coolant is cooled by a radiator, yes? When I did my Thermodynamics module of my Mech Eng degree, our tutor did a lecture along much the same lines as this video. I must admit though, I did give the front face of my IC a light dusting of black spray paint, but only so it looks better behind the black grille. Jason, do you think you could do a video of the ways you can improve the efficiency of a stock intercooler? I've recently moved my Saab 9-3's IC from the middle of the cooling pack (sandwiched between the condensor and radiator) to the front of the cooling pack so it gets ambient air. The improvement in intake temp control when pressing on is fantastic - this is defo the BEST ZERO COST mod I've ever done. Yet the derrision I get from other owners on the Saab forums is incredible. As far as they are concerned the ONLY worthwhile mod is to fit an Evo FMIC. They just can't (or won't because they want to justify the money they've spent) believe the stock IC can be improved at very little cost. One of these days I'll get round to doing a video of the mod for my channel.
3% of a larger number may have been significant, but with the MCM example of 97-degrees (C) versus 100-degrees (C) IS negligible. THAT 3% difference equates to only about 5-degrees (F) under air-flow (convection) conditions. The 39-degree (C) improvement under heatsoak conditions to ME is a stronger argument, and to me provides a much greater advantage over a 5-degree (F) loss. That's about a 70-degrees (F) improvement, btw. Also, I do believe BMW paints their factory intercoolers black.
You don't need to reduce the intake charge temp if you're not moving. You're also not creating boost if you're not moving, and thus not compressing the air (and increasing it's temp).
Couldn't the paint simply be a fashion statement? And/Or to keep the aluminum from oxidizing maybe even increasing the thermal conductivity? I'd have look at aluminum oxide conductivity... but it's hard so I'm guessing it's not very conductive. Just some thoughts.
Engineering Explained you should really do a video on the thermal effects of heatsoak after sitting at the lights or a drag strip... than youll have a real conclusion... the debate is still half open, more types of driving suffer from heat soak conditions compared to continual air flow... unless ur straight out track racing or fwy cruising how long do u actually sustain a high psi period for?? 400m at a strip... and how ever far you can on the street, then back to heatsoaking again... each situation is individual but im with mcm on this as heatsoak occurs alot more then airflow, mind you im not going out painting my ic anytime soon... if its that big of a deal to any one, you would jus go water injection...
When you talk about these kind of numbers on this kind of setup you shouldn't expect linearity on the differences between them; when conditions get harshest, f.e. going high speed up a mountain on warm weather, the painted intercooler will reach its empirical heat-dissipation ceiling much faster, over which things will start to look nasty for the rest of the engine. The reasons behind this are not only related with the temperature gradient formed on the paint layer, but the change in material rugosity due to the paint layer would be quite relevant at high air speeds, both of which affect the convection process. Also this limit is not a hard-knee bent, and you would start to see it's effect much earlier, where the gap would widen in bigger and bigger percentages as more heat dissipation is demanded. About the no-airflow part of the experiment, I would like to know how the thermocouples where placed on the painted intercooler, cause in such a experiment, with natural convection in play, the aluminum thermal conduction plays the biggest role, and if they just placed the thermocouple on top of the paint then you may just be quantifying the thermal insulating properties of that particular layer of paint. If it was indeed well positioned, I would still look at natural convection and conduction mishaps, as radiation should ammount to the smallest heat dissipation of the three available. Really nice videos from both MCM and EE, mythbusting is always an involved task, but a necessary and rewarding one at the same time.
ok, what if the intercooler is anodized in black? It´s not black paint, it´s the alluminium itself turned in black. will it affect the convection tranfer of heat?
Anodizing a colour into something still involves another component, it's not paint exactly, it's more of a dye. The anodizing process purely by itself simply increases the thickness of the oxide layer on the surface of the part. The thicker oxide layer is then capable of "absorbing" the dye. But yeah, good question, I'd like to know the answer too. :)
"Anodizing (also spelled anodising, particularly in the UK, India and Australia) is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts." Its adding / thickening the layer on top of the metal, not changing the metal itself. Think of it as very thin paint put on with electricity.
But it would still be black instead of reflective. So it would absorb more heat. Everyone knows that the inside temperatures of black cars get higher when left in the sun then the inside temperature of white cars. That's just basic science dude. It may not make much difference. But there is no way in hell it would improve the heat transfer..... (which is the whole point to the theory....)
the last time i heard of physics was about 20 years ago in school and now i see a guy in front of a whiteboard telling my physics. first thought it could be boring, but no! i love it good work :)))
What about a black anodized surface finish? I don't know if the aluminum oxide layer would slow the heat transfer at the surface... Also what about a really rough surface finish for more surface area and turbulent airflow?
I'm curious about that as well, but from what I know Anodizing is staining a pre-existing layer in the metal and not creating any additional layers. so it should perform the same, except in direct sunlight.
8 лет назад+4
I had the same thought... What about say an anodized Al cooler or coating the cooler in a coating that is conductive and pebbled so as to increase the surface area? Glad I'm not the only one with that crazy idea...
Depends on what's in the paint. If the paint is mixed with bits of Graphene it would definitely be more of a heat conductive paint than an insulator. Graphene is really good at conducting heat and electricity. It's also a really new material so not sure if anyone has made a paint with it yet. The research that I have run across has said that there's a great possibility that Graphene paint could be used as a Paint on Solar panel. If used with an intercooler you'd be able to charge your battery and keep the intercooler cold.
8 лет назад+3
Well I know ASUS uses "Cera-mix" coatings on their "Sabertooth" motherboard heatsinks because of the whole "increased surface area" I'm just not sure if the same coating or even the same concept would work on an intercooler.
I forgot about ASUS doing that. I guess there is only one way to find out at this point. I don't have a car with a turbo so I can't test it. I wonder if ASUS would be willing to help get the project start. Testing there Cera-mix on a larger scale may get more promotion for them along with proving that their "mix" works.
They did a similar test with an aircooled motorcycle engine in one of the motorcycle magazines decades ago and proved to my satisfaction that this video is correct. Painting the engine's cooling fins looked really cool, but the measured cylinder head temperature was quite a bit higher. I think the manufacturers of radiators painted their radiators because they used to be made of copper or brass and needed the corrosion protection. Everyone got used to radiators being black and might have erroneously assumed they were painted to help cool.
You can't argue with thermodynamics. Well, not unless you have a carefully worked out experiment that shows some element of it to be wrong with a high signal to noise ratio and the approval of a peer review body. #science
I have to say I think despite the 3 degrees difference with air flowing the resting air flow I think for town driving would make it worthwhile. A 3 centigrade difference on the move will make virtually zero difference to power, however if the intercooler is placed in an area where it wont soak much of the heat from the engine, a 40c difference would be felt when pulling away after being stationary for some time. Lets not forget, manufacturers don't want to add additional manufacturing processes and costs.
I love MCM too, but they have a history of their mythbusting episodes being wrong. They allege that a stock intake system is the best for power, and I'll concede that with some cars this is sometimes true if you have an aftermarket filter by itself. However, there are cars where modifying the engine and retaining the stock intake can literally cause damage because it can't get enough air, or enough cold air, let alone reduced performance. But I also have a car with a black factory radiator.
desertfox2020 Alone they are correct, and technically they are still correct no matter what UNLESS you get your car tuned for the mod. Tuning is the key, a cold air intake with a tune will net about 10hp vs a tune without the intake. For a stock tune, the majority of mods can end up harming the vehicle and/or reducing power.
nutnfan1 But that's really not true. Depending on the design of the stock intake and the demands of the engine, anything which can flow more will help. The Nissan VQ is an example of an engine where an aftermarket intake will COST you several horsepower because the stock one has a ram air scoop and works very well. For example my car has a supercharged 3800 V6. By replacing the stock intake with a cone filter ALONE is worth quite a bit, because the cooler, larger volume of air allows less detonation under boost. It also depends on the car how much you can mod without a tune. A Subaru needs a dyno tune if you look at it sideways but a lot of domestic cars will adapt to aftermarket parts fairly quickly.
desertfox2020 Funny you mention that since I am a Subaru owner (and I wholeheartedly agree). lol And the VQ engine could get a similar benefit from a cold air intake that draws from outside the engine bay as well. Saying anything for sure for all vehicles is kind of tricky; cars are VERY situational dependent, agreed?
nutnfan1 Definitely agreed. Sometimes two cars of identical make, model, year, engine and transmission respond differently to the same mods under the same conditions.
desertfox2020 They literally have minds of their own. The ECUs make adjustments for what it thinks the car should be running at, and will actively tune themselves within a range to "correct" for what the mod is doing (cough cough my subaru cough).
I know, but pretty much all computer aluminum heatsinks are anodized, and while it is an oxide film, it is also going to be very thin and consistent. Not to mention, aluminum while not easily oxidized, it still needs a protective film to prevent gradual and uneven oxidization.
+David Wei Yes but with computer parts makers focus more on looks because you don't expect sun blasting the heatsink directly and it won't get heated as much from other parts as long as the case is provided with good airflow.
+David Wei Anodizing is very thin (< 0.001" thick) and still a decent thermal conductor ( see alumina ceramic) Looks however you want it to, and shouldnt affect performance measurably. Anodize it whatever color you want.
You do a great job of delineating the the different types of thermal energy transfer such that the layperson can understand that there are different ways that heat behaves.
Engineering Explained Wait. You live in Oregon? I've been following you for over a year and have never know this. I'm gonna be looking for your STi now. Haha.
+BeyondTheRedLine Anodizing only slightly increases the thickness of the oxide layer that already occurs on aluminum. I doubt you'd see a significant difference in efficiency either way.
I appreciate what they're trying to do at mcm but I always feel like I'm watching silly flat earth experiments without proper scientific method. They're interesting to watch but its cringy seeing the conclusions they come to sometimes.
Glad you mentioned space, the ISS cooling system is fascinating. They circulate ammonia through the radiators, it has a high specific heat capacity and can operate in the low temperatures of the radiators without freezing. But they are white? Yes, it's a special high emisivity paint which rejects energy at very specific wave lengths. Thanks for the talk, I love thermodynamics.
Let's face it, The guys at Mighty Car Mods don't know basic physical science... They should have learned the difference between convection and radiation in high school.
Hi EE. I had the privilige to attend a heat transfer class taught by Yunus Çengel in his home country at Ege University where I got my Bioengineering degree and PhD. He is a great teacher. It's also cool that we have something in common. Keep up the good work! PS. even though I don't own a car I enjoy watching your videos an feel like I won't be doing all those worng stuff once I have my car.
I love your videos and only just stumbled across this... Best one by far!! Not only did I learn something new, but I saw your humour come out too. Your comment about a Chimp not being as good at explaining how an intercooler works using a whiteboard had me cracking up!! Ha ha ha
Surely spray paint decreases the thermal conductivity, but what about thermal dispersant coating that comes on some intercoolers? Does it actually improve heat transfer as they claim? Anyway, even plain aluminum intercoolers must have some sort of coating, or they would oxidize, right?
@Engineering Explained - emmisivity is only one component. There are multiple elements at play here. Manufacturers DO in fact annodize intercoolers and radiators in black to increase heat transfer. -why? 1) The thickness of ceramic used in anodizing is extremely thin. So even if it has a low k value (20 vs 200 w/mK), the thickness is such (talking 50nm several microns) that it has a negligible effect on the overall heat transfer coefficient. 2) On the microscopic level the anodizing creates microscopic fissures or “pores” on the surface. This creates, strangely enough, more heat transfer surface area. 3) The black color aids in radiation heat transfer by increasing the emmisivity of the radiator or intercooler. You are correct that these heat exchangers are designed for convection, but they are still undergoing all three forms of heat transfer simultaneously (even if convection is dominating). This small difference factors into an overall more efficient heat exchanger. 4) Bare aluminum will oxidize naturally anyways. Better to control that oxidation in a way that gives you beneficial heat transfer properties. Love the videos. Studied heat transfer extensively at university and now professionally. Keep up the great work!
I really enjoyed this video, it reminds me of watching mythbusters and imagining that it would be a much better show if they had a mathematician or physicist on the team because they sometimes (though rarely) end up testing the wrong thing or getting the myth wrong. One small thing that confused me a lot learning about thermodynamics growing up is that people talk about convection as a distinct process, like you can have convection without electromagnetic radiation. Radiators are very good at transferring heat to the air within them via radiation, so much so that the air quickly reaches temperatures close to the radiator temperature and now there's nowhere for that radiated heat to go. So good radiators are limited by, not based on, their ability to convect that hot air away, which is why that's the thing to optimise.
Mighty car mods may have considered how the essential role of convection in an intercooler but were just trying to start a trend with modified car owners like themselves and that was their message at the end of their video as the difference between stock and painted was insignificant (to them at least). Both Engineering Explained and MCM videos are amazing keep it up guys!
My question, long hand. Since the raw Aluminum will soon oxidize and make a coating of aluminum oxide, essentially glass, a poor conductor of heat. At this point would the blackened one (the Back Body) then become the more efficient of the two? For real reliability both coolers should be coated for protection from oxidation. To make this even again we should have them both anodized. I would suggest Clear anodizing on one and black anodizing on the other. Both coolers will now equally coated and the black should be more efficient. What do you think now?
Being an engineer myself since the 90s, there's a flaw with this video in regards to the color of OEM intercoolers and radiators and AC condensers as being silver / raw Al. The OEM color on Dodge Ram Cummins components is black and have been black since the 90s. The fins, the core, the tubes and piping of all cooling components are black vs. bare Al. I've got two Dodge Ram's here, 2005 Cummins and one 96 gasser that has black everything down to the gear box oil cooler. I've also got two Mitsubishi jeeps types of vehicles in the bay here both, sporting black rads, and coolers. I've also got one Kia 2016, also sporting a black rad and oil cooler. Other than that error in generalization, the rest of the video is informative. I've seen the original video of the car mod video and was satisfied with the results using Matlab. I get where you're coming from as well regarding a "coating" as, I'm an EE dealing with ridding thermal heat in Aerospace Electronics used in Space so, I get where the mindset is on that however, in real-world applications in Automotive applications, black finish seems to be common.
I'm an Engineer, I painted my intercooler black, but not for performance. This car is a sleeper ;) Having said that I never thought about the heat transfer disadvantages and I am surprised it performed worse in flow situation, given that house wall poly bead insulation and windows give better performance if they are coated for radiation reflection. I guess the main lesson is that houses aren't an air flow situation in the cavity at least. In my case I do worry about the proximity of the front mounted radiator to the cooling system radiator (which is black by the mfr BTW and also operates at 100C), so I left the back of it unpainted and created as much space behind it. The test also wasn't totally realistic because of the lack of pressure (the cause of the heat in the first place), so I wonder if the thicker air might make a difference, and explain why car water radiators are painted black. (although to be fair aluminium ones are not so it might just be a corrosion coating).
I enjoyed both videos! I understand when you said that the intercooler is not designed to dump heat via radiation. However, it appears to me that if an intercooler were to have radiating heat loss properties, it wouldn't be a bad thing. Both videos looked at painting intercoolers. The first video showed a painted temperature decrease without airflow and a temperature increase with airflow. It appears to me that all we have answered so far is if paint decreases convection efficiency. How would we be able to measure convection efficiency if the aluminum was anodized? If it is unaffected, is there potential we've added radiative properties to the intercooler without a loss of convective efficiency? Thanks!
In reference to the test done in the video, I believe your conclusion is correct. However, reason does exist for a "black" intercooler to perform better than a natural intercooler. The aluminum oxide formed naturally is an insulator. A manufacturer could use a coating such as MIL-DTL-5541 Class 3 and the add a graphite paint over the top to protect the Chem film which should greatly increase conductivity.
Thank you for your contribution to the post-modern enlightenment so needed in our technological world. Science illiteracy is a genuine problem in even the most sophisticated societies. Professors are often preoccupied with the fundamentals (ex. using conservation laws to breed useful equations) which are completely necessary and valid. But I find that explanations like yours using "intuition pumps" (As coined by Dennett) combined with real science fidelity in plain spoken English is what will inspire the next generation of engineers and STEM enthusiasts. People like you make these daunting topics very accessible. (On a personal note; As a mechanical engineer who used Cengal and Boles for my thermodynamics classes as well, it's so pleasant to have your excellent videos buttressed with familiar variable convention.) You are making humans just a bit better as a species. The noblest pursuit.
Starts watching video about painted intercoolers, learns why polar bears don't get cold in the wind
+RoyalSilver&Gold Can I borrow this please?
+RoyalSilver&Gold Brilliant!
+logan buck if only other people realized the same works for dogs, so they dont need to freak out when they see dogs out in someones yard on a winter day. Many dogs (especially ones with thicker fur) prefer to be outside to cool off.
And polar bears are painted black, so they absorb more of the sun light - the fur is actually channeling the light onto the skin. Polar bears are so cool on many levels!
Multitasking 😁
Great video man. Very enjoyable. And I think we almost came to the same conclusion, that with airflow there was a negligible difference. But with no airflow, we saw, and measured a significant difference. We stand by the results we achieved on the day, though we can't be sure how the results will apply to each persons circumstance.
One important point and comment is that you stated that car manufacturers don't make black radiators and went on to say "Does this mean major car manufacturers don't understand emissivety?" But a huge amount of cars do have black radiators. It would be interesting to know why?
We're really glad our original video has inspired a lot of debate, conversation and education - it's exactly why we do these kinds of videos. You should jump onto the MCM forum and add to the discussion. There's a 10 page thread on this topic already. Hopefully we'll see you there! Cheers!
Mighty Car Mods I was hoping you guys would show up! :D I was thinking throughout the whole video about how he doesn't mention the advantage in no airflow. For me, a commute with stop-and-go traffic, I see an advantage, and will be painting it black on my Subaru when I get the time to dismantle the thing.
Lol you stand by the results I just lost a whole lot of respect for mcm he explained radiation and convection theres no point in having a cooler intercooler if you not on boost/ not moving
Like come on at least have the balls to say your conclusion was wrong....
Jeremy quiring It's not all about power, turbocharged cars are very fuel efficient. A smaller motor can make the power of a big motor, but only when needed. Sitting at idle or low speed with a lower intake temp is a benefit for my fuel economy, as my engine can use even less fuel to maintain enough power to idle. Also, in a drag race, staging (vrooom popopopopopop) a turbo car can see benefits on the line from a cooler intake temp. Just depends, clearly there are advantages and disadvantages to this mod. Decide for yourself what your car might need.
I respect both youtube channel but I don't know who to trust. Mighty Car Mods need to DYNO the Sliver and Black Intercooler to back up their claims with more empirical evidence.
Wood floats on water. Ducks also float on water. Therefore ducks are all made out of wood.
Nice reference
basic logic principles. i love doing this in arguments
Monty Python at their best.
What about small rocks?
Video is correct! Stop insulating your heat expelling components!
Best finish would be clean/polished aluminum.
Next best finish (it won't look corroded in a few months or corrode and crack/fail in areas where water/dirt/salt can collect in the fins) would be anodized aluminum as while anodizing is also insulating, it is far far thinner than any kind of paint (and also lighter BTW).
It is also very hard and abrasion resistant.
Read up at en.wikipedia.org/wiki/Anodizing under 'Sulfuric acid anodizing (Type II & III)'
'Type II Coatings of moderate thickness 1.8 μm to 25 μm (0.00007" to 0.001") are known as Type II in North America, as named by MIL-A-8625'.
Yep - as thin as 7 one hundreds of 1 thousands of an inch (or 7% of 0.001" - difficult to measure) up to one thousands of an inch of an aluminum oxide layer that can be uniformly and consistently be coloured (BLACK? or a hundred other colours - RED perhaps?, or just natural aluminum - the colouring won't effect final coating properties except for the MAAAD results) in the anodizing process (colouring won't change the thermal conductivity).
I've had a few VW (1983 to 1997) and the aluminum rad cores have NEVER failed. The joint between the AL rad core and the thermoplastic end caps has always been the point of failure.
Problems - anodizing is a thermal and an electrical insulation so modifications (welding on/fixing brackets) requires a bit of grinding/sanding to remove the anodizing in that location (same as you'd remove paint in that area) which ruins the anodizing in that area.
Aluminum pop/beer cans have a total PAINT thickness (inside and out) of about one thousandths of an inch (25 μm - pretty good and uniform but not abrasion, corrosion weather resistant). Anyone with any kind of spray on paint will NEVER be able to provide a consistent thickness of paint over the huge area of the inter-cooler 'tubes' and paper thin fins as it is nearly impossible to paint the deep recesses created.
Paint sticks much better to an anodized AL surface than a bare aluminum surface unless using a specific bare AL primer (ANOTHER layer of paint - the primer - is counterproductive for heat transfer).
Absolute best - car that never sees anything other than the track or lives in a desert - BARE ALUMINUM.
Next - Anodizing AFTER all bracket modifications, etc have been performed.
Next - anodize all over, tape off the inner part of the inter-cooler (inner tubes and fins) and spray paint the OUTER surfaces of the inter-cooler.
As an engineer you have no idea how good to hear someone
1) Make sense
2) Explain and recherche and back up his idea with ACTUAL real knowledge....
3) I love that book!!!
4) Thermo at work!!!
Jamal Chehab Woo!
i hate that book
Jamal Chehab lol finals exam on thermo next week, wish me luck
Recherche, thw covfefe of engineers.
As a very well read ex-physics student gone machinist, I would like to add 2 very important points to Engineering Explained's video. Normal black paint has a high emissivity in the VISIBLE spectrum. A car intercooler never gets hot enough to emit radiation in the visible spectrum! It is highly unlikely that whatever black paint is being used is 'black in the infrared' too - the intercooler will only emit radiation in the infrared, hence the idea of using black paint is a moot point from the beginning. You would want a coating that has an absorption spectrum from 700nm to 1mm lambda. Point 2 is something you never went over, and that is why their intercool was more efficient without airflow with black paint than without paint. The answer is simple: The solvent in the paint must vaporize/flash off in order to dry. When this is happening, there is a phase transition from liquid to gas, which absorbs heat from the immediate substrate (the intercooler) in order to accomplish the phase transition. THIS is why the intercooler was cooling so much better at first with the black paint and no air flow! The paint drying was sucking the heat off of it!
+DjRjSolarStar Indeed, the only way they could have been so wrong in their results is if they ran their 2nd 'test' before the paint was completely dry. Evaporative cooling FTW. Moral of the story: Mechatronics engineer should stick to mechatronics.
Now, we have the complete picture :) I'll copy/paste your post so others can read it.
DjKinetec ok
DjKinetec nice! So paint the intercooler silver just before you hit the drag strip lol. Love it, though!
@@WadeOntheLure I get the joke :) But on a serious note you can spray water on the cooler to increase the efficiency.
If you were a teacher in my science class, when I was in school, I would've enjoyed it a lot more. You're awesome at giving information in a way that it's fun to pay attention and learn. Thank you for doing what you do
Amen!
No good teacher teaches..they got much better jobs..lol
OhighO Skater : Agreed! He's awesome for knowing and sharing all kinds of stuff we want to know. Potential youtube god status
@@ryanwells5035 Also agree, which accentuates the fact he's awesome for taking the time to make these vids
I would be bored to death in his class of babbling!
I'm not a mechanical engineer and I thought painting the intercooler black was obviously going to yield worse performance. Good video though - I wasn't expecting to learn as much as I did, and you did a great job at proving someone wrong while being perfectly humble about it.
Blows me away that anyone would think that painting something black would help cooling. If you want a better intercooler put away the rattle-cans and go air-to-water. I thought the original idea behind painting intercoolers black was to help hide them in sleepers.
nearly ever electro motor is painted black due to higher radiation
John, 100% correct. I gave mine a wafer thin black dusting only for the stealth look.
Lol. Radiators have been painted blk for decades and still are blk. Figure 🤔
345 people have painted their intercoolers black
They idiots
Actually most Montune and Cobb intercoolers come with some portion of black, Montune is completely black. These companies actually employ ME's with automotive backgrounds. This is just like buying a shirt in the hot summer, you can go with the white Hanes tee-shirt or a identical tee-shirt made the exact same but is dark blue with the Hoonigan slogan on the the front. You will pay more money for darker Hoonigan shirt, since it's the same shirt you are paying for a logo and the Suns heat will heat up the more expensive shirt. It is all in branding and what people think is cool. Intercoolers are ultimately made of raw aluminum, but can sell an inexperienced modifier a black one for an extra 50$, or whatever.
some people paint them black for stealth...
Even companies do it from factory, the new Ford focus RS which makes way more horsepower than any subaru.
The Focus RS also includes a plate to make the intercooler even less efficient than just painting it black. Therefore all intercoolers should have blocking plates? Being an owner of the Focus RS, I'm here to tell you, this car is not made for track driving at all.
"A hot sunny night...." Ah, I often have those where I live.. Lol
I came here to comment the same thing!
i was about to say, "is that a reference to a inside joke concerning fireworks?" lol
+sean25351 sorry you're having such a miserable day you gotta take everything the wrong way. hope it gets better for ya!
+sean25351 yeah I'm sure that's what happened. piss off.
+D Stingray summer night... you dumbfuck
OK, after watching the MCM video I think I figured out why they got such an improvement from painting the intercooler (during the no fan test). It's because the the intercooler is covered in fresh paint. (they even made a point of putting a ton of paint on the thing) And that paint is still evaporating it's solvents. So it is not just giving off heat by radiation. It is also evaporating, and of course there is some airflow due to convection. Given enough time to cure, a week a month... the advantage of the fresh paint will disappear. And the 3% gap seen with airflow will widen.
Oh, and of course, painting the intercooler black does not eliminate the original surface of the intercooler. It's still there, and must now transmit it's heat to the paint.
"HOT SUNNY NIGHT" LOL
I think they call that "day"
@@inufreak483 that depends on where you live, if its light at midnight is it day or night?
@@jaydunbar7538 You're right! If you're far enough north, it doesn't get dark in the summer, that's why Yukon is called the land of the midnight sun.
"then why do you have a campfire"
I thought I heard wrong!lol
I can say with first hand experience that major automotive manufacturers do in fact paint intercoolers, radiators, and condensers black. Its 100% for looks. You are correct that this does slightly diminish the returns of the heat exchanger, the parts are generally designed with this in mind. Also, when paint is applied, its done in a very thin layer to reduce the loss in efficiency, and to not coat the inner portions of the fins or tubes where most of the surface area is. So yes your right that its better to leave the metal bare, but the losses shouldn't be significant due to a light coat of paint.
Source: I work for a major OEM parts manufacturer where these components are made and some are painted black as well.
Awesome, thanks for sharing!
Ever so negligable and no real significant bearing on performance unless you are aiming for a 1000 of a second finish at the tracks 😅😅
I just got finished testing both of my intercoolers (Twin Turbo side mounts) I left one as is and I coated one with thermal dispersant paint. To those that argue that coating the IC will create a thermal insulator, consider the material you are using...if the coating has a specific heat capacity that is better than the substrate, you will conduct in the direction of the coating. If it is worse than the substrate, you will insulate that substrate. I ran a test similar to mighty car mods but with better controls. Instead of running an ambient fan I built a shroud to activate the intercooler cooling surface (this is equivalent to the car moving). Might Car Mods is hyper-focused on emissivity when there are other factors that cause the improvement in IC efficiency. Without Coating, We heated the intercooler body to 185F. The Instantaneous Peak IC Inlet Temp vs Output temp was 82 Deg F. With Coating, the Delta at the same IC heat soak peak temp was 135 Deg F. This is almost a 40% reduction in temperature! The coating is designed to increase conduction and convection of heat and this simulation depicts conditions of what happens in intercoolers after an increase in turbo boost. The result is that the coating gives one's vehicle a better margin of safety against potential pre-ignition/detonation due to high engine inlet temps. This also means you can run higher boost pressures for better performance. The test setup had thermocouples in ambiet air 5 feet away from the test rig and an additional TC in the fan shroud 5 inches from the IC's cooling fins(inside of the fan shroud). The other 3 were at the IC's inlet, Halfway through the IC cooling fin body (inside of the fins) and the last one at the outlet. All equipment was Calibrated. Equipment used: Degree ATM 2400 and USB UTS100T thermocouples.
"If its a hot sunny night then I dont know why you have a campfire." I died of laughter!
Great video. I just put a fat Turbo on my Polaris RZR 900 and everyone and their brother says i should paint it black (my intercooler). F that...the first thing i thought to myself was that the paint will act as an insulator and on top of that, mine is in direct sunlight so it would also absorb heat as well. I am not an engineer so if someone like me can figure out that basic common sense, i wonder why others seem to think different? The mighty car mods thing is good to i agree because they are awesome but your's is a more logical explanation of what is happening. Oh, and you just earned yourself another subscriber - thanks!
meade916 Thanks for subscribing! Awesome channel by the way, I've watched quite a few of your videos!
Engineering Explained haha, right on man, good to hear that!!! I appreciate it man and now that i found you ill be watching quite a few of your's! Love your channel!
"I am not an engineer so if someone like me can figure out that basic common sense, i wonder why others seem to think different?"
I am an engineer, and the answer is: Application. For engines that make boost at low rpm, like superchargers or even many modern turbos, the 60% increase in heat transfer at these low rpm and low vehicle speeds can be a boon for the 0-60 and 1/4 mile times. That 3% loss would be an issue on the circuit, however, as the vehicle relies on mid and top-end power.
What say those of the half-brother persuasion @paint?
Engineering Explained i actually ended up painting my intercooler....but not to gain any heat dissipation which i know won't happen. I did it for looks. Even though i am sure some of the paint got inside the fins, we specifically didn't soak the crap out of it and focused on just the outside area so i could get a logo stenciled in. If you look close at it you can see the aluminum inside the core still. So I know i said i wouldn't do it but i mainly did it knowing it probably won't help but also that it really shouldn't hurt much either. I stuck 2 giant fans on the intercooler as well where i never had them before so it should be good to go i think.
When I finished watching their video a few weeks ago the first thing I wondered was what you'd have to say about their conclusion. You are like a younger Bill Nye. It's one thing to know your stuff but the real talent is making it understandable to non engineers & you sir are awesome at it. I've subscribed for years & keep coming back for more.
Thanks! Bill Nye has always been an inspiration. Like the master himself, I only have a bachelors of science in mechanical engineering. An interesting fact on the guy. I appreciate your viewership!
3:33 hot sunny night :D
well yes, in the northern hemisphere you get midnight sun in the summer, wich means the sun never sets it happens here in the northern part of sweden.
DyingCr0w Here in Finland.
NJHS92 uhhhh... “in the northern hemisphere”. No.
In the Arctic circle.
But not just that, same thing happens in the Antarctic circle.
Night - noun - 1. the period of darkness in each twenty-four hours; the time from sunset to sunrise.
How can it be night if the sun didn't set?
Colin Griffin well technically, the sun is out even at night. Unless it's a full moon (or new moon? Can't remember which one is pitch black lol) as the moon light is simply just a reflection of the sun's light lol. Same way as you would say "he pointed a laser at my eyes" even if it wasn't laser to person, but rather laser to mirror to person.
2 minutes of silence to those who painted their intercoolers black.
Mads Filholm well the difference is very small between the 2 so if they did it for design probably it worth it I guess.
Here is a challenge; see if you can spot a black intercooler in any form of motor sport ? Or any OEM ? No, I didn't think so.
Nor Dic BA Ford Falcon XR6 Turbo
Nor Dic
89-03 (1st and 2nd gen 12v Cummins add 2nd gen 24v) are aluminum supplyed to dodge painted black...
I have a 91.5 that is tore down to receive an 03 IC both stock black. I guess this makes Cummins/ Dodge a minor OEM ... I'm in agreeance shame on them for having painted these black.
Ford Focus RS also uses a black intercooler. Even if the difference is negligible it does look pretty cool.
As a fellow engineer I have to say that I absolutely love your videos, you're one of the few YT sources that actually has knowledge of the engineering, physical phenomena and practical knowledge of cars.
I salute you! :D
Black intelcooler - more effective.
Red car - faster.
Yellow suspension - stronger.
Chrome exhaust - louder
Flame stickers + 10 hp
Fake air vents +15 hp
Polished turbo, +15% airflow
yellow brakes - stronger*****. blue suspension - smoother*****
Surf board size rear wind : Magnetic Traction on 20 mph turns..
dice valve stem: +20% grip
Radiators in cars used to be black when they were made of copper. Now they are aluminium they are silvery. Probably because copper needed painting to stop it corroding. The aluminium is protected from corroding by an oxide layer that is increased in thickness by anodising, it would be easy to anodise them black, without any insulating effect if it made a ha'porth of difference. Which it doesn't, so they don't.
Any water or oil cooled engine has no radiator it has a heat exchanger.
@@rustybeatty6567 Whats the difference?
Redd's laws of thermodynamics:
1) You can't win (you can't get more energy out of a system than you put in, conservation of energy)
2) You can't break even (Friction, loss, etc. you will always have less energy out than is put into a system, entropic principal)
3) You can't leave the game (Unless we find another universe with completely different rules, and even then it's not very likely that you could circumvent rules 1 and 2 in any universe conceivable that contains matter)
+ReddmanDGZ ok
Your statements are very true and very misleading (not true) at the same time:
- "you can't get more energy out of a system, than you put in" - complete nonsense, we both know that, right? I can trigger a process, using a small amount of energy, for a much larger energy transfer from the environment. Just like a heat pump does. Or a transistor. Or an implosion atomic bomb. The true statement would be "you can't get more energy out of a system, than WHAT'S ALREADY IN IT". Doesn't matter how much you are putting in. The environment could be putting in a LOT more, than you are.
- "you will always have less energy out than is put into a system" - Exactly correct. Notice, how this statement contradicts the very first one directly. In majority of cases, there is an additional energy being delivered from the environment anyway, in the form of heat (infrared), microwaves, x-rays, etc.
- "you can't leave the game"... What game?
@TheRadiastral The energy is already there for those things, you're forgetting that you also put the materials (therefore the mass/atomic bonds) into the system.
This reminds me of the guys who argue "hella flush stance" improves their vehicles handling abilities.
I already feel smarter and I like the way you set out your vids and how you explain everything on the board.
I also think it will be really cool to see you modifying the integra but with your added knowledge and take on things.
Good luck with furure vids!
Since I discovered your channel, I rarely watch other channels based on car modifications.
Black intercoolers on many 80s and 90s JDM cars - Impreza, Legacy, Skyline, Supra, plenty more. The Lancia Delta HF Integrale too. After the 90s, I can't think of any. Did they get smart or are they doing it for good looks? I don't know.
Though this does bring to mind drilled rotors on new cars.
it appears from the MCM video that if you want better performance while stationary then the black intercooler is the one for you!
I believe most people want performance while they're moving. ;)
+Engineering Explained oh there's a market for everything :p .. great channel btw, I've learned lots.
+Matthew Papowski They must wanted it black for that S2000 so when it breaks, it runs cooler on the side of the road.
Well i think stationary performance is often called "swag" or more accurately "looking cool". As the word "cool" suggests, cars with higher stationary performance run cooler all around. Sounds completely logical right?
+Engineering Explained Great video. I understand the Intercoolers & Radiators function - BUT why not have a intertwined radiator built into the intercooler? One water channel, one air channel and so on... OR will the hot turbo air heat the water and thus cause the air to remain hot?
Should have said "If it's a hot sunny night, I don't know what universe you're living in"
PixelCortex I can't guarantee my words will always be great.
+PixelCortex Or you're in Alaska in summer time.
+Engineering Explained You should do a video explaining how you would have a hot sunny night in which people would be around a campfire.
+PixelCortex I believe a sunny night is called day
+PixelCortex he dosent have to be on a warm universe I guess you havent heard of the places on earth that have sunlight all day ;)
Cengal & Boles- same thermo book I used at University of Portland nearly 20 years ago. Very well done (especially compared to my confusing Shigley machine design book). I remember one of the problems in the book was calculating black vs. chrome cooling fins on an air-cooled motorcycle engine like a Harley (no cooling fan). At speed, convection overwhelmed radiation and made it negligible, but at idle where you have only natural convection, there was a small but significantly useful advantage to the black fins...something like 10% or less. A 10% advantage is important if you're about to overheat in traffic. They probably would've been closer to 10% without the insulating layer of paint.
A black intercooler might slightly help your intercooler while you're stopped, particularly if you anodize it instead of painting it, but it won't make a difference once you're moving so probably isn't worth the effort. Also, it's been a while, but shouldn't you have used absolute temperature?
To be honest, I think the biggest issue that needs to be discussed in this is ducting and not the painting. 90% of the time I would say lack of proper ducting far greater outweighs the 3% difference in temperature.
I can't even count how many intercoolers that mostly are just stuck in the front of the car and not properly ducted. And that ducting is to be applied on both sides ( air being rammed through the front of the car at speeds, as well as the fan being properly ducted to pull at idle properly.)
I haven't done any testing properly, but I think that should be done in 3 tests though, one with just a fan stuck on there, second one with a fan with a fan shroud bolted on, and thirdly with the fan and shroud sealed with tape or foam tape to ensure all corners are properly air sealed.
Lastly before getting back into painted vs non painted, another big factor that I often see is lots of fins being bent. Even a slight bend can reduce the flow pretty drastically. Its not uncommon for me to see radiators and intercoolers with probably about 10% of the fins bent in ( or actually on the topic of fins, being filled with bugs or dirt and grime) that would far out weight the paint discussion.
Now to get to the heart of the the topic, I do have some issues with "jumping to conclusion " that a painted intercooler, vs a non painted one actually makes a difference. There are lots of open loops here, one there's a big difference in entirely painted (think of it dipped into a paint tank and then pulled out) the other part could be just lightly painted to change the frontal color ( keep in mind , probably over 99% of the non painted surfaces are still bare aluminium. ) One major factor plays here in regards of that and that is core thickness. The thicker the core, the less the percentage of the painted area is in the case of spray painting the front faces to non painted is).
Another angle to consider is age. As the cores age, oxidisation occurs on the bare aluminium. Does this oxidisation layer make the core less or still "more" effective than a painted one that may have oxidised less over the year due to the protection provided by the paint.
... In summary, painted or not, that is the least of any of the major issues to be concerned about in regards of a cooling effect of radiator or intercooler.
But are they wooden duct's.And do they float, Hmm
lol once I saw the title of this video, I can Imagine Engineering Explained watching the MCM video and thinking: "Fuck... I don't want to have to do this... Seriously? Looks like I'm going to have to bring out the whiteboard"
Haha it wasn't how I planned on spending that day. :)
I worked manufacturing high end radiators and intercoolers for mining equipment (mainly). ALL were painted black before being bolted together with the condenser (and sometimes even fuel coolers, often only seen on the really big rigs used to do outback trucking).
Link really ? No motor sport of any type has black intercoolers.
Imagine that 3% at 70mph on the highway! Just a tiny fan produced a temperature difference of 3 degrees C. I would imagine that the amount of air flowing through an intercooler on a drag strip going 90mph would be significantly higher and that 3 degrees would be multiplied tenfold.
Completely agree!
Engineering Explained Now imagine if the intercooler was 30 degrees cooler before it had 90 mph winds blowing through it on the drag strip, you know, because of less heat soak from idling in the staging lanes for 20 minutes...
If the MCM data is correct, then the intercooler will be 30 degrees cooler at the starting line. The air going through the intercooler isn't going to cool it 30 degrees in 10-15 seconds the car is moving down the strip, especially since the car will be at full boost the whole pass.
Not saying your video is wrong, I just want you to mythbust the advantages of a black intercooler reducing heat soak.
cody clark Well, if you think about it this way;
If black radiates but also absorbs heat more easily, the intercooler may well heat soak faster if it is in the engine bay near to things that radiate a lot of heat.
Furthermore, if the air temperature around is hotter than or close to the temperature of the air flowing through it (in the case of the air intake location being cooler air, or air at the same temperature as the intercooler's location), the intercooler will probably not cool the air very much through radiation because it's close to being in equilibrium, the heat wants to flow from an area of high concentration to an area of lower concentration.
In the MCM video the heat soaked intercooler was on a table at room temperature which is basically best-case scenario for allowing the heat to radiate, in a real car the situation is not likely that ideal, being close to hot blacktop and possibly an exhaust manifold.
If, for example, you had a black and a raw aluminum intercooler in the same place on identical cars lined up at the strip (for worse case scenario, think subaru top-mount, or a front mount on a honda that sits very very close to the exhaust manifold and very close to a hot road surface, where the radiant heat will be at it's worst) you would expect the aluminum intercooler to heat soak more slowly because the radiant outside of the intercooler is greater than inside. It would also cool down faster as the car pulled away down the strip.
The only way it would be better would be if it was a very cold day, and mounted far away from anything under the hood that would radiate heat, and also not in direct sunlight. However, that improvement would come at the cost of making the car perform worse in hot conditions and in convection at speed.
I think, anyway. It would be fun to test this with a car like the 300zx twin turbo because it has side mount intercoolers and the turbo system for each cylinder bank is a mirror image of the other, so you could paint one side and not the other.. and test the results.
I agree, but I would have argued with the mcm's results if I hadn't seen the video proving that the black intercooler actually lowered the boost air temps without air flow. I would like to see a test with the black intercooler with higher ambient temps to see if it really does help with heat soak.
That was very comprehensive. Maybe a little too comprehensive. Since it's a hot sunny night, I'm going to go sit by my campfire now.
"Conclusion: Do not paint your cooler black."
But I don't want people to know I'm packing.
Deadass lmao
Use a liquid to air chargecooler and you'll be sneaky AF....
"If it's a hot sunny night, why have a campfire?" I laughed.
For the marshmallows, of course.
"If it's a hot, sunny night" Wait a second...
I love this video! Seriously!
Great video! "the more worthless the system is" LOL I love the side commentary.
A little different take. My old competition drift car (pro am) I painted the back-side of the intercooler and radiator, but left the front side bare.
Drift cars you RAIL on them, then you sit in staging and wait to get launched again; this is where we see immense heat soak issues arise.
Logic behind painting back side, is the frontal (front half) of heat exchanger surface areas remain un-insulated, so where the temperature differential is the highest there is also minimal insulation. On the back side (also in the dark in the engine bay) it is black, this is where we want more radiative based cooling since we aren't moving, and everything is hot from a hard run, now bleeding heat into everything. We want the heat exchangers cool when we get launched so we don't feel a power loss, as this will change how you need to drive.
New comp car, the heat exchangers are left polished for aesthetics, and water sprayers are installed, so when the car isn't moving we can spray water via button onto heat exchangers and allow evaporation to help disseminate thermal energy. (I'm assuming you like this method much more lol) Running Ethanol for fuel which burns colder also helps keeps temps lower. Effective ducting, and division of air channels so heat exchangers don't share air also helps.
Anyway side tracked now.
Great video. You should be lecturing at Uni (if u aren't already). There is a real knack to being able to explain physics/engineering concepts- well teaching anything really,in general, and you have that knack.
Just wanted to point out that the mighty car mods test showed that the black radiator radiates heat better with no airflow but performs worse with airflow
Because of the insulation, yes. More air flow means more work to cool it that doesnt work..maybe a water pump spray that is temp regulated?
+ThoughtElevator: LOL
Thermodynamics and fluid mechanics is one of the hardest things we learn at uni, but its definately one of the most interesting! Loved this video
I would say they're the hardest of the core mechanical engineering curriculum. The senior and upper division / elective engineering courses, which build off of the basic principles of thermo, heat transfer, and fluids are way harder.
So an automotive radiator isn't actually a radiator? More like a convection....ator?
Correct, and really convection in this sense is simply conduction with the air moving.
EE - Going to mess with some of my mechanic friends. lol
Check your personal Facebook (other messages) sent you a message about Engineering degrees etc. My initials are DH just in case you have quite a few messages.. Thank you. Awesome videos.
very informative info the one thing that i love in automotive engineering is usually the name of a part dictates it purpose/function amazing that it should actually be called a convection/er?
sounds more appropriate
@@aussieguy1012 except for backlight being the descriptive term for rear window ...
finally a good video maker that can actually explain things subscribing
Thanks for subscribing!
np man love the vids I understand everything a lot better now
+Burak Keles what do you mean finally, where have you been, Jason is already a legend.
lol
I enjoyed thermo too. As an engineer I sometimes forget what is such an obvious thing to me (from my education) and not to others. good video explaining. Its funny how often car trends are really bad for performance. Now I gotta go watch mighty car mods to see this.
There are aplenty of cars that come with black intercoolers. R32 - R34 GT-R, XR6 turbo comes with black intercooler just to name a few. For street applications, removing the black paint off a GT-R intercooler sees an INCREASE in average intake air temps. This is because there is no fan on the intercooler and only works when moving. On the street you are stopped a lot.
***** Do you have info to back up the "increase" of intake air temps?
Engineering Explained
Sir - Engineer to Engineer - Well explained :) I watched the MCM video and immediately went "meh". I thought it obvious that radiators are convective devices :)
I'm thinking now about the R34 and the Ford Falcon XR6-Turbo. Okay - they are indeed black. But they also appear to be anodised. I'm assuming they do this to maintain a known condition of the metal - over time the metal would oxidize and become *slightly* less effective.
So rather than a big, thick layer of paint - what about anodised aluminIum? Whilst it won't be as effective as bare metal, the process will keep that metal as effective for longer.
Yes MCM is correct in their verdict, even i can feel the differance in power on my v4 wrx sti when heat soaked
still waiting for info of so called "increase" of intake, im also interested
isaac j
:D very funny
Another mechanical engineer here, here's my two cents. Painting an intercooler in the hope of performance gains is misguided, and that's well explained in the video. One thing that wasn't totally covered is just how insignificant radiation is in a system like this (VERY). But it's a good video. However a lot of people are looking for the aesthetic effect, since an unpainted aluminium fmic is not to everyone's taste. If you paint the front surface only, so that only the leading edges of the fins are painted, you will get virtually the same aesthetic effect and it will have minimal effect on heat transfer, since most of the surface area of the fins will remain unmodified (all the heat transfer work is done on the surfaces parallel with the airflow, the parts of the fins you can't really see, which have enormous surface area). You would be painting a fraction of a percent of the surface area. Obviously it would have to be done by hand as opposed to spraying. Personally I would leave the intercooler alone and go with a dark grille in the bumper in front of it. It will tone down the look of the car and protect the fragile fins from being damaged by road debris. Over time you get enough dents and that will drop the efficiency of the heat exchanger substantially, as the airflow between the fins gets blocked/disrupted. So add a grille, it's functional and you can adjust aesthetics with it without goofing around with important engine parts.
+Faketrollname sevenbillion Kind of a random question here from an engineering student, but one thing I've always wondered is why they don't use the hood for cooling? Construct it from aluminum and put fins on it like a heatsink. Wouldn't that eliminate the need for airflow through the engine bay, and reduce some drag?
decidiousrex Because you couldn't transfer enough heat fast enough from the block, through the air, into the hood. If you decided to use a coolant fluid to get the heat up there, it would be more complication than it was worth, as the system would need to detach when the hood was opened, and finding a location for the expansion tank would be hard. If you did figure out some way to get the heat up into the hood that was simpler than a normal system, you would then have to figure out what to do when the car was static (natural convection isn't enough), which would mean a fan drawing air over the hood, and I'm not sure how you'd package that. The fins on the hood would make engineering for pedestrian safety more complicated. I'm not saying it's impossible, but those are a few drawbacks I can think of.
Faketrollname sevenbillion Definitely some obstacles I didn't think of. That's more of an idea I thought of while in the shower than a seriously thought out plan. I'm sure if the saving in drag (if there is any) outweighed the added complication, automakers would be using that system.
I'd rather see thermoelectric power generation used to cool cars, unfortunately the tech simply isn't there right now. Maybe someday....
+decidiousrex I had a coleg how said that there are sport motorcycles that use the body of the bike as a radiator with integrated pipes but is very expensive to repair if damaged. I am not sure if is true, not sure if I remember corectly.
+Adrian Draganescu , this is true of the Harley V-ROD. Only that the oil from the engine and water is going through part of the cycle FRAME like a water jacket. I added an optional oil cooler ( like a black small intercooler ) to dissipate heat while on the road between Houston , Tx and Arizona. It helps drop the temp in the engine by at least 10 degrees. It comes anodized black just to match the bike. JK.
I don't get it? Looking at the formula, 1.03 is the Q for no2, not no1. Surely the rate of heat transfer is higher for the black intercooler as it has rejected more heat to atmosphere than the silver one with all other things being equal. An IAT of 97 is better than 100, so it's more efficient. Please can someone explain why I'm wrong? Cheers, Tom
Excellent video although I don't know anywhere on earth you can have a hot sunny night. You can have sunny night near the poles (if you base night on time of day) but I wouldn't exactly call it hot.
+Nan0Scho1ar just give it a couple more years. ;) It was a joke, also.
Hahaha I didn't even realize, I thought it was just a slip up but it seems the joke went straight over my head. Keep up the good vids :)
I had a sunny night (22:00) in Helsinki recently and it was kinda hot (24 C)
That MCM video also made me cringe a bit. What they seemed to fail to realize is that an intercooler is mainly used to cool air that was heated by using forced induction (turbo, supercharger). When your car is standing still, you have no boost, and no need of it, so there is also no super hot air to cool.
Yes indeed! Great point to add.
I really enjoyed the breakdown on painting coolers in general. I was skeptical about purchasing a painted one. Thanks again!
Just a thought on the "3%" difference.
Shouldn't you be using Kelvin, not Celsius? I'm not sure if anyone has pointed this out yet but really the difference would be 373/370 (1.008, so 0.8%) not 100/97 (1.031, or 3.1%)
Thoughts on that, Engineering Explained?
If you a calculating one temperature minus another the result is in Kelvin. E.g. 20°C-10°C=10K
(20+273)-(10+273)=10K.
But if the result is in Kelvin then to have it as a percentage of the original temperature, the original temp. has to be in the same units.
Otherwise it's like saying 50 miles is half of 100km
Adam Hansen in this case it's the change in temperature that matters not the temperature itself, a change of 97C would be the same as a 97K chane where as a room at 97C is equivalent to a room at 370K. basically these two temperatures changes in kelvin would be 97K and 100K = the same thing
mastafixa I understand that Kelvin and Celsius use the same increments, but Kelvin starts at 0 whereas Celsius starts at -273.
My point is that in SI units, Kelvin is used not Celsius or Fahrenheit.
Mauswerkz said this in the MCM video - Around about the 8:30 mark "That doesn't necessarily mean it's doubled it's efficiency though?" "No, it's not twice as efficient just because you've seen double the difference; it doesn't work that way with Celsius."
Temperature is a measurement of vibrations in molecules (as I understand it) so higher temperatures = more vibrations and lower temperatures = less vibrations right the way down to absolute zero where the vibrations stop altogether, which is at 0K or -273.15°C
The vibrations CAN'T reach a negative amount so in this application, to calculate the percentage difference between the two results you have to use a scale that starts at zero, so you must use Kelvin.
The difference between 97K and 100K as a % difference is NOT the same as 97°C vs 100°C. I know the difference is 3K or 3°C because they use the same increments but percentage wise they are very different scales.
When you said "Hot sunny night" 3:30 lol
In the arctic circle the sun stays above the horizon 24/7 in summer time. In winter it doesn't go above the horizon, it's dark 24/7. :)
DG At least till the axis turns :)
Just helped two people decide to purchase a silver intercooler over a black one for our VW GTIs, by showing them this video. Great job again sir! Extremely useful info
Great way to clear up the confusion. Love your videos!
Unfortunately they are not right. And their own numbers show that. 97 : 100
^ doesnt understand math
***** You are right. I would prefer 100 degrees. Thus the SILVER intercooler. Thus they are not right in stating that the black intercooler is better and their own numbers show that. ("They" and "their" are Mighty car mods of course. I guess we got confused because my comment was a response to someone saying "but might car mod proved it", which was later deleted.)
Gunfu Brizzo Why exactly?
I know this is an older video, but I was wondering if you know why almost all radiators for warercooled pc's (which use fans to cool them) are black? Would this be purely aesthetic, or do you know if there are examples of paint which interfere so little with the air flow that the emissivity of the black paint and the heat lost through this could positively effect rate of heat transfer. i.e a paint so thin that the pros outweigh the cons...
Tom Eiseman good question, I'd also like an answer.
billy653 I can probably answer this. It's the same reason almost all radiators in older cars are painted black. Copper. Copper has been the material of choice for radiators for a long time, but the issue with copper is it readily oxidizes. So manufacturers coat them in black paint to protect the copper for the atmosphere.
Pony Power
Ah good call. I haven't sand blasted a computer rad, I just know all the automotive rads that are copper are painted black.
+Pony Power That's far too fast to jump to a conclusion there. It strongly depends on the manufacturer of the radiators. For example Alphacool is always using copper for their radiators with a really thin black layer on the outside, but NOT on the fins of the rad. (See topic of insulating layers)
So just saying they paint it for hiding bad quality is bullshit and probably only counts for cheap rads where common sense already tells me that a cheap rad will be manufactured cheaply.
Also, Alphacool already sells white radiators. The colour design of those radiators have to match as many PC-builds as possible, else they wouldn't sell enough units and the most neutral colour that in 99 % of the cases fits to any colour-scheme, is black.
Hey Dr Cengel, the other author of that book, was my thermodynamics teacher at University of Nevada Reno. He's a great guy and I like his book too.
Shouldn't you do 373K/370K? Or is the formula designed to work with degrees C?
Doesn't matter ^^' ! I mean it's a delta so it gonna be the same in °C and in K
+pokk700 But I agree because K is the internaltional unit so ...
+pokk700 no, because the change in temp is 100K and 97K respectively.
+MadJEFF I'm not a scientist, but I'm pretty sure most formulas are designed to work with degrees K, because the Celsius scale doesn't exactly correspond with the energy of a system. For example, because the Celsius scale can be negative, a body at 25 C actually contains about 92.2% of the energy of a similar body at 50 C. With Kelvin, because the scale bottoms out at 0, a body at 25 K contains 50% of the heat energy of a body at 50 K. This makes the math a lot easier.
+pokk700 That triangle symbol by the temperature, delta, means difference. We're talking about differences here, not absolute magnitudes. And a difference of 10 degrees K (or C, same thing) is the same no matter where you place 0.
It's a hot sunny night in here... :D 3:28 :D
That made me laugh. I wonder if he meant to say it on purpose, or if it was just a slip of the tongue.
doing the same. Check. Carry on.
...Happens in Pokemon
3:32
even after 4 years I find this video is still one of my favorites. I even linked it to a thread wherein a vendor was answering me as to why the intercooler (being offered for sale) was painted black:
"purely for looks" was the reply. That's when I posted the link to this video. I suppose marketing trumped science in that decision-making exercise. Always good to learn from someone who brings
science to the discussion.
2 vids in... subscribe you make my brain tingle.
Thanks for subscribing! Hope you enjoy the tingle.
r32 gtr, r32 gts, all gc8 wrx's and more all have oem black IC's. Its mainly to be less noticeable.
Brilliant, brilliant BRILLIANT
The number of stand up aguements I've had with people who swear you should paint them black! the trouble is people are mixing up and confusing radiation and convection. After all, your coolant is cooled by a radiator, yes?
When I did my Thermodynamics module of my Mech Eng degree, our tutor did a lecture along much the same lines as this video.
I must admit though, I did give the front face of my IC a light dusting of black spray paint, but only so it looks better behind the black grille.
Jason, do you think you could do a video of the ways you can improve the efficiency of a stock intercooler?
I've recently moved my Saab 9-3's IC from the middle of the cooling pack (sandwiched between the condensor and radiator) to the front of the cooling pack so it gets ambient air. The improvement in intake temp control when pressing on is fantastic - this is defo the BEST ZERO COST mod I've ever done. Yet the derrision I get from other owners on the Saab forums is incredible. As far as they are concerned the ONLY worthwhile mod is to fit an Evo FMIC. They just can't (or won't because they want to justify the money they've spent) believe the stock IC can be improved at very little cost. One of these days I'll get round to doing a video of the mod for my channel.
3% of a larger number may have been significant, but with the MCM example of 97-degrees (C) versus 100-degrees (C) IS negligible.
THAT 3% difference equates to only about 5-degrees (F) under air-flow (convection) conditions.
The 39-degree (C) improvement under heatsoak conditions to ME is a stronger argument, and to me provides a much greater advantage over a 5-degree (F) loss.
That's about a 70-degrees (F) improvement, btw.
Also, I do believe BMW paints their factory intercoolers black.
You don't need to reduce the intake charge temp if you're not moving. You're also not creating boost if you're not moving, and thus not compressing the air (and increasing it's temp).
Couldn't the paint simply be a fashion statement? And/Or to keep the aluminum from oxidizing maybe even increasing the thermal conductivity? I'd have look at aluminum oxide conductivity... but it's hard so I'm guessing it's not very conductive. Just some thoughts.
Engineering Explained you should really do a video on the thermal effects of heatsoak after sitting at the lights or a drag strip... than youll have a real conclusion... the debate is still half open, more types of driving suffer from heat soak conditions compared to continual air flow... unless ur straight out track racing or fwy cruising how long do u actually sustain a high psi period for?? 400m at a strip... and how ever far you can on the street, then back to heatsoaking again... each situation is individual but im with mcm on this as heatsoak occurs alot more then airflow, mind you im not going out painting my ic anytime soon... if its that big of a deal to any one, you would jus go water injection...
When you talk about these kind of numbers on this kind of setup you shouldn't expect linearity on the differences between them; when conditions get harshest, f.e. going high speed up a mountain on warm weather, the painted intercooler will reach its empirical heat-dissipation ceiling much faster, over which things will start to look nasty for the rest of the engine.
The reasons behind this are not only related with the temperature gradient formed on the paint layer, but the change in material rugosity due to the paint layer would be quite relevant at high air speeds, both of which affect the convection process. Also this limit is not a hard-knee bent, and you would start to see it's effect much earlier, where the gap would widen in bigger and bigger percentages as more heat dissipation is demanded.
About the no-airflow part of the experiment, I would like to know how the thermocouples where placed on the painted intercooler, cause in such a experiment, with natural convection in play, the aluminum thermal conduction plays the biggest role, and if they just placed the thermocouple on top of the paint then you may just be quantifying the thermal insulating properties of that particular layer of paint. If it was indeed well positioned, I would still look at natural convection and conduction mishaps, as radiation should ammount to the smallest heat dissipation of the three available.
Really nice videos from both MCM and EE, mythbusting is always an involved task, but a necessary and rewarding one at the same time.
Intanius You can use Celsius for a delta T (T°-T°), it doesn't make a difference on the result.
ok, what if the intercooler is anodized in black? It´s not black paint, it´s the alluminium itself turned in black. will it affect the convection tranfer of heat?
Yes. Anodizing is an insulating layer but far thinner than any paint.
Anodizing a colour into something still involves another component, it's not paint exactly, it's more of a dye. The anodizing process purely by itself simply increases the thickness of the oxide layer on the surface of the part. The thicker oxide layer is then capable of "absorbing" the dye.
But yeah, good question, I'd like to know the answer too. :)
"Anodizing (also spelled anodising, particularly in the UK, India and Australia) is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts."
Its adding / thickening the layer on top of the metal, not changing the metal itself. Think of it as very thin paint put on with electricity.
But it would still be black instead of reflective. So it would absorb more heat. Everyone knows that the inside temperatures of black cars get higher when left in the sun then the inside temperature of white cars. That's just basic science dude. It may not make much difference. But there is no way in hell it would improve the heat transfer..... (which is the whole point to the theory....)
No motor sport of any type does this.
the last time i heard of physics was about 20 years ago in school and now i see a guy in front of a whiteboard telling my physics. first thought it could be boring, but no! i love it good work :)))
"Hot sunny night"
Not one of my brightest moments. Oh bad puns...
Hey could be that way in Alaska
well if it in Siberia :)
Black intercoolers matter.
ALL intercooler matter... Seriously. Pay attention to your intercooler
@@johnboltz3591 RIP to every turbocharged car owned by somebody who doesn't know what a turbo is
👀
Great explanation. Very clear and complete. The part with the chimp was definitely convincing that 3% could be a big difference. Well done.
What about a black anodized surface finish? I don't know if the aluminum oxide layer would slow the heat transfer at the surface... Also what about a really rough surface finish for more surface area and turbulent airflow?
I'm curious about that as well, but from what I know Anodizing is staining a pre-existing layer in the metal and not creating any additional layers. so it should perform the same, except in direct sunlight.
I had the same thought... What about say an anodized Al cooler or coating the cooler in a coating that is conductive and pebbled so as to increase the surface area? Glad I'm not the only one with that crazy idea...
Depends on what's in the paint. If the paint is mixed with bits of Graphene it would definitely be more of a heat conductive paint than an insulator. Graphene is really good at conducting heat and electricity. It's also a really new material so not sure if anyone has made a paint with it yet. The research that I have run across has said that there's a great possibility that Graphene paint could be used as a Paint on Solar panel. If used with an intercooler you'd be able to charge your battery and keep the intercooler cold.
Well I know ASUS uses "Cera-mix" coatings on their "Sabertooth" motherboard heatsinks because of the whole "increased surface area" I'm just not sure if the same coating or even the same concept would work on an intercooler.
I forgot about ASUS doing that. I guess there is only one way to find out at this point. I don't have a car with a turbo so I can't test it. I wonder if ASUS would be willing to help get the project start. Testing there Cera-mix on a larger scale may get more promotion for them along with proving that their "mix" works.
"Hot, sunny night."
I love sciencey people :)
They did a similar test with an aircooled motorcycle engine in one of the motorcycle magazines decades ago and proved to my satisfaction that this video is correct. Painting the engine's cooling fins looked really cool, but the measured cylinder head temperature was quite a bit higher. I think the manufacturers of radiators painted their radiators because they used to be made of copper or brass and needed the corrosion protection. Everyone got used to radiators being black and might have erroneously assumed they were painted to help cool.
Waiting on the MCM response.
You can't argue with thermodynamics. Well, not unless you have a carefully worked out experiment that shows some element of it to be wrong with a high signal to noise ratio and the approval of a peer review body. #science
What if wrapped it in aluminum foil to further increase it's % of aluminum?
Engineering Explained I'll do it. Thanks for the instructions.
I have to say I think despite the 3 degrees difference with air flowing the resting air flow I think for town driving would make it worthwhile. A 3 centigrade difference on the move will make virtually zero difference to power, however if the intercooler is placed in an area where it wont soak much of the heat from the engine, a 40c difference would be felt when pulling away after being stationary for some time. Lets not forget, manufacturers don't want to add additional manufacturing processes and costs.
I love MCM too, but they have a history of their mythbusting episodes being wrong. They allege that a stock intake system is the best for power, and I'll concede that with some cars this is sometimes true if you have an aftermarket filter by itself. However, there are cars where modifying the engine and retaining the stock intake can literally cause damage because it can't get enough air, or enough cold air, let alone reduced performance. But I also have a car with a black factory radiator.
desertfox2020 Alone they are correct, and technically they are still correct no matter what UNLESS you get your car tuned for the mod. Tuning is the key, a cold air intake with a tune will net about 10hp vs a tune without the intake. For a stock tune, the majority of mods can end up harming the vehicle and/or reducing power.
nutnfan1 But that's really not true. Depending on the design of the stock intake and the demands of the engine, anything which can flow more will help. The Nissan VQ is an example of an engine where an aftermarket intake will COST you several horsepower because the stock one has a ram air scoop and works very well. For example my car has a supercharged 3800 V6. By replacing the stock intake with a cone filter ALONE is worth quite a bit, because the cooler, larger volume of air allows less detonation under boost. It also depends on the car how much you can mod without a tune. A Subaru needs a dyno tune if you look at it sideways but a lot of domestic cars will adapt to aftermarket parts fairly quickly.
desertfox2020 Funny you mention that since I am a Subaru owner (and I wholeheartedly agree). lol And the VQ engine could get a similar benefit from a cold air intake that draws from outside the engine bay as well. Saying anything for sure for all vehicles is kind of tricky; cars are VERY situational dependent, agreed?
nutnfan1 Definitely agreed. Sometimes two cars of identical make, model, year, engine and transmission respond differently to the same mods under the same conditions.
desertfox2020 They literally have minds of their own. The ECUs make adjustments for what it thinks the car should be running at, and will actively tune themselves within a range to "correct" for what the mod is doing (cough cough my subaru cough).
what about anodized black instead of paint?
I agree painting it black is stupid, since I just can't imagine any kind of conductive paint....
+David Wei anodisation is oxidised metal so wont be as good for convection
I know, but pretty much all computer aluminum heatsinks are anodized, and while it is an oxide film, it is also going to be very thin and consistent. Not to mention, aluminum while not easily oxidized, it still needs a protective film to prevent gradual and uneven oxidization.
+David Wei Yes but with computer parts makers focus more on looks because you don't expect sun blasting the heatsink directly and it won't get heated as much from other parts as long as the case is provided with good airflow.
+David Wei Anodizing is very thin (< 0.001" thick) and still a decent thermal conductor ( see alumina ceramic) Looks however you want it to, and shouldnt affect performance measurably. Anodize it whatever color you want.
You do a great job of delineating the the different types of thermal energy transfer such that the layperson can understand that there are different ways that heat behaves.
Hell no, I'll paint it pink if I want to lol
Just saying around 3:34 few seconds before you say. if its hot sunny night...think about it sunny night?
Haha well here in Oregon in the summer we lose sunlight close to 10 pm. Though ultimately it was a joke - funny or not. :)
I wanted to say that
Engineering Explained Wait. You live in Oregon?
I've been following you for over a year and have never know this.
I'm gonna be looking for your STi now. Haha.
I knew it didn't quite make sense. Nice one EE, everyone painting their intercoolers needs to see this.
@0:20 did he said Michael Pools or Balls?
+Agustin Cesar *Boles.
+Engineering Explained russian accent... balls.. lol.. english accent.. bowls..
+Engineering Explained What about black anodized intercoolers?
+BeyondTheRedLine Anodizing only slightly increases the thickness of the oxide layer that already occurs on aluminum. I doubt you'd see a significant difference in efficiency either way.
I appreciate what they're trying to do at mcm but I always feel like I'm watching silly flat earth experiments without proper scientific method. They're interesting to watch but its cringy seeing the conclusions they come to sometimes.
Glad you mentioned space, the ISS cooling system is fascinating.
They circulate ammonia through the radiators, it has a high specific heat capacity and can operate in the low temperatures of the radiators without freezing.
But they are white?
Yes, it's a special high emisivity paint which rejects energy at very specific wave lengths.
Thanks for the talk, I love thermodynamics.
Let's face it, The guys at Mighty Car Mods don't know basic physical science... They should have learned the difference between convection and radiation in high school.
Mmm look at you all big with your 1 sub.
Damm that escalated quickly
Ito Ke
Congratulations on not understanding how RUclips subs work
3:31 "If it's a hot sunny night... I don't know why you'd have a campfire" HAHAHA! Good one ;)
Hi EE. I had the privilige to attend a heat transfer class taught by Yunus Çengel in his home country at Ege University where I got my Bioengineering degree and PhD. He is a great teacher. It's also cool that we have something in common. Keep up the good work!
PS. even though I don't own a car I enjoy watching your videos an feel like I won't be doing all those worng stuff once I have my car.
I love your videos and only just stumbled across this... Best one by far!! Not only did I learn something new, but I saw your humour come out too. Your comment about a Chimp not being as good at explaining how an intercooler works using a whiteboard had me cracking up!! Ha ha ha
My favorite line... "if it's a hot SUNNY NIGHT". I love you man. I just had to laugh.
Surely spray paint decreases the thermal conductivity, but what about thermal dispersant coating that comes on some intercoolers? Does it actually improve heat transfer as they claim? Anyway, even plain aluminum intercoolers must have some sort of coating, or they would oxidize, right?
@Engineering Explained - emmisivity is only one component. There are multiple elements at play here.
Manufacturers DO in fact annodize intercoolers and radiators in black to increase heat transfer. -why?
1) The thickness of ceramic used in anodizing is extremely thin. So even if it has a low k value (20 vs 200 w/mK), the thickness is such (talking 50nm several microns) that it has a negligible effect on the overall heat transfer coefficient.
2) On the microscopic level the anodizing creates microscopic fissures or “pores” on the surface. This creates, strangely enough, more heat transfer surface area.
3) The black color aids in radiation heat transfer by increasing the emmisivity of the radiator or intercooler. You are correct that these heat exchangers are designed for convection, but they are still undergoing all three forms of heat transfer simultaneously (even if convection is dominating). This small difference factors into an overall more efficient heat exchanger.
4) Bare aluminum will oxidize naturally anyways. Better to control that oxidation in a way that gives you beneficial heat transfer properties.
Love the videos. Studied heat transfer extensively at university and now professionally. Keep up the great work!
I really enjoyed this video, it reminds me of watching mythbusters and imagining that it would be a much better show if they had a mathematician or physicist on the team because they sometimes (though rarely) end up testing the wrong thing or getting the myth wrong.
One small thing that confused me a lot learning about thermodynamics growing up is that people talk about convection as a distinct process, like you can have convection without electromagnetic radiation. Radiators are very good at transferring heat to the air within them via radiation, so much so that the air quickly reaches temperatures close to the radiator temperature and now there's nowhere for that radiated heat to go. So good radiators are limited by, not based on, their ability to convect that hot air away, which is why that's the thing to optimise.
Mighty car mods may have considered how the essential role of convection in an intercooler but were just trying to start a trend with modified car owners like themselves and that was their message at the end of their video as the difference between stock and painted was insignificant (to them at least). Both Engineering Explained and MCM videos are amazing keep it up guys!
My question, long hand. Since the raw Aluminum will soon oxidize and make a coating of aluminum oxide, essentially glass, a poor conductor of heat. At this point would the blackened one (the Back Body) then become the more efficient of the two? For real reliability both coolers should be coated for protection from oxidation. To make this even again we should have them both anodized. I would suggest Clear anodizing on one and black anodizing on the other. Both coolers will now equally coated and the black should be more efficient. What do you think now?
Being an engineer myself since the 90s, there's a flaw with this video in regards to the color of OEM intercoolers and radiators and AC condensers as being silver / raw Al. The OEM color on Dodge Ram Cummins components is black and have been black since the 90s. The fins, the core, the tubes and piping of all cooling components are black vs. bare Al.
I've got two Dodge Ram's here, 2005 Cummins and one 96 gasser that has black everything down to the gear box oil cooler. I've also got two Mitsubishi jeeps types of vehicles in the bay here both, sporting black rads, and coolers.
I've also got one Kia 2016, also sporting a black rad and oil cooler.
Other than that error in generalization, the rest of the video is informative. I've seen the original video of the car mod video and was satisfied with the results using Matlab.
I get where you're coming from as well regarding a "coating" as, I'm an EE dealing with ridding thermal heat in Aerospace Electronics used in Space so, I get where the mindset is on that however, in real-world applications in Automotive applications, black finish seems to be common.
I'm an Engineer, I painted my intercooler black, but not for performance. This car is a sleeper ;)
Having said that I never thought about the heat transfer disadvantages and I am surprised it performed worse in flow situation, given that house wall poly bead insulation and windows give better performance if they are coated for radiation reflection. I guess the main lesson is that houses aren't an air flow situation in the cavity at least.
In my case I do worry about the proximity of the front mounted radiator to the cooling system radiator (which is black by the mfr BTW and also operates at 100C), so I left the back of it unpainted and created as much space behind it.
The test also wasn't totally realistic because of the lack of pressure (the cause of the heat in the first place), so I wonder if the thicker air might make a difference, and explain why car water radiators are painted black. (although to be fair aluminium ones are not so it might just be a corrosion coating).
I enjoyed both videos! I understand when you said that the intercooler is not designed to dump heat via radiation. However, it appears to me that if an intercooler were to have radiating heat loss properties, it wouldn't be a bad thing.
Both videos looked at painting intercoolers. The first video showed a painted temperature decrease without airflow and a temperature increase with airflow. It appears to me that all we have answered so far is if paint decreases convection efficiency. How would we be able to measure convection efficiency if the aluminum was anodized? If it is unaffected, is there potential we've added radiative properties to the intercooler without a loss of convective efficiency?
Thanks!
The chimp analogy rocks! I'm still wiping the tears from my eyes! Hilarious. The video content first class as always! Thanks
In reference to the test done in the video, I believe your conclusion is correct. However, reason does exist for a "black" intercooler to perform better than a natural intercooler. The aluminum oxide formed naturally is an insulator. A manufacturer could use a coating such as MIL-DTL-5541 Class 3 and the add a graphite paint over the top to protect the Chem film which should greatly increase conductivity.
Thank you for your contribution to the post-modern enlightenment so needed in our technological world. Science illiteracy is a genuine problem in even the most sophisticated societies. Professors are often preoccupied with the fundamentals (ex. using conservation laws to breed useful equations) which are completely necessary and valid. But I find that explanations like yours using "intuition pumps" (As coined by Dennett) combined with real science fidelity in plain spoken English is what will inspire the next generation of engineers and STEM enthusiasts. People like you make these daunting topics very accessible. (On a personal note; As a mechanical engineer who used Cengal and Boles for my thermodynamics classes as well, it's so pleasant to have your excellent videos buttressed with familiar variable convention.)
You are making humans just a bit better as a species. The noblest pursuit.