I wasn't sure if I was gonna sub to this channel before, but seeing that in the end, there was no question anymore. Every good video has at least one badly 'disguised' knob in it. 10/10
Just discovered this guy and he's the first RUclips car guy I've seen caveat literally every idea for car aerodynamics. When he introduced who NACA was instead of just saying a NACA duct sucks in air, I knew he's the real deal.
My neighbour is nearing 90 years old, he's an aero engineer who has consulted extensively since his retirement in his mid 70s. He's sharp as a tack and still gets calls from DoD colleagues when they are stuck. I was stunned when he told me about some of his colleagues in the 1950s joking about their previous work... "Ze guidance has to be so accurate now, my last boss vas happy as long as ve hit London"
since it was (as i recall) more than 80 german and austrian high profile scientists and engineers back then, probably. Von Braun died in the 70s as i remember 😅 And we just start building inflatable space stations. He would be so bored.
I burst out laughting everytime you showed Kermit flailing his arms around to display turbulent flow. This is one of the best, most visual descriptions I've head and I'm going to use it from now on!
17:00 if you're in the UK the custom is to attach a small bell at the front to get a sense for how much the air is flowing, this also helps you remember which end is the front. It's the bellend.
They say some people are innately qualified to be employed as the measuring device instead of the bell. Unfortunately for them, it seems to coincide with having not exactly stellar character traits.
The Dodge Charger Daytona and Plymouth Superbird, Chrysler's NASCAR homologation efforts around 1970 used textured vinyl on their roofs. This served two purposes, first the rough texture did have a "golf ball" effect which helped stabilize a shape that was never designed to go 200 MPH. And second and perhaps more importantly, it covered the slapdash bodywork done to the 2500 street versions they had to try to sell. NASCAR banned vinyl tops for 1971.
Everyone always asks if I ever took an aerodynamics class in engineering school. Of course I tell them I did, but the class was not whatever they imagine aerodynamics to be. It is a dark art, with understanding inversely proportional to knowledge.
As a senior engineer of a wind tunnel for a major automotive OEM, I can confirm. Since I've been doing this job for 11 years, I'm regularly labeled "aerodynamicist" which is a term I hate. It implies that I know something about aero, but most of my job consists of me saying, "who knows? Let's just test it to find out."
I did take aerodynamics in engineering school. It's remarkable how much of the earlier course work focuses on "these are the general ways that these idealized perfect shapes act in a perfect airflow that has no entropy or flow separation". The later course work is focused on "And this is a simplified view of how the real world makes all of that stuff weird and not as usable as we led you to believe". Even worked for a brief spell at a wind tunnel, where it turns out that even the advanced coursework's simplified real world stuff we learned was only a little bit helpful, especially as you get further from idealized conditions.
Thank you , as an armchair aereodynamicist who just enjoys learning about aircrafts i was always stunned when things i learned where contradicted later on , So ye , i should probably get a real hobby
It's good to know that all fields of engineering have "that one branch" which is all a black art; I still recall when I first started to understand how RF circuits worked in theory and went "Aha!" and then realized that actually building them was a completely different thing...
Probably one of those things that is significantly different between hydrodynamics and aerodynamics, but one of the things we have found in racing sailboats is that a slick, glossy hull surface is often slightly less performant than a sanded, matte surface. Something about the roughened finish wetting, making the dominant interaction be water on water instead of water on fibreglass. The Olympic Soling class used this to great advantage; you could tell pretty quickly who sanded their hulls and who polished them. The sanded hulls were usually a boatlength or two ahead consistently.
Surface tension in hydrodynamics is very different than the surface tension in aerodynamics... Well, different probably isn't the right word but the forces are vastly different in strength.
The same interaction between hull and water is interesting in that the object is to reduce the wetted area of the hull to reduce friction . On powerboats air is ducted in from the chines located at the steps to induce a carpet of bubbles that the wetted surface is in contact with . On sail boats where regs do not permit such devices , the introduction of a rough surface creates microbubbles of air which unstick the wetted area . On WLSRs you are actually trying to make the boat fly but keep contact with the water . Compared to air ,water is a high viscosity fluid which causes plenty drag . Renato "Sonny" Levi was the first to recognise this creating the Levi Delta common in most planing hulls sometimes combined with a conical form to create the ' conical delta' hulls . In an inlet port with a mixture of fuel and air a polished finish produces poorer flow and less bhp than a port finished with 60 grit cones to maintain good turbulence by mini vortices and attachment to port walls . Its good to polish the exhaust as a) the exhaust gas is forced out and b) it delays build up of fouling .
Although the fluid difference is very significant, the same effect does occur in air. I think it is worth examining whether laminar or turbulent flow is idea for different areas of the body.
Comparing water and air is closer than it would appear when the velocities are high. Air gets VERY hard to push through and if you start to apply serious power to something it's going to heat up. Wonder if a pressurized boundary layer type skin wouldn't help with the friction losses. Maybe only need the pressurized (or even suction) panels here and there to really clean up the profile.
I was thinking about the golf ball aerodynamics all along the video. Never saw the Mythbuster episode but I saw a research video on golf ball aerodynamics that compared even dimples vs random size and distribution of dimples. Very happy that you saw the question coming.
After reading up on theory and (tested) examples on an ecomodding website, I made some aero mods to my 2005 Accord to reduce its drag (for fuel efficiency reasons, not speed). I did A-B-A-B testing during relatively stable weather. Runs in both directions, straight level road, no traffic, using cruise control with the car left on for consistent speed. Short airdam w/ curved lip connected to a partial undertray under the engine bay, partial grille block, side mirrors folded back. Could add/remove all at the side of the road with simple tools. Got ~4.25% fuel efficiency improvement at 55mph. Pretty happy with that.
About 20yrs ago I cut up 200 ft of 1/4 clear vinyl tubing and ran it from inside my 66 Belvedere hardtop to points all over the body. Base of the windshield, grill, fenderwells, area behind rear window, and like that. Then I had my buddy Sam drive me around on I-81 at 80mph while I hooked up each tube to a furnace exhaust stack vacuum gauge and wrote all the results down. My plan was to figure out where the high and low pressure areas were so I could see if there was any way to duct the high pressure air to the low pressure areas to reduce drag or make it rain behind the car or something. The only thing the experiment indicated might be helpful was to remove all the glass from the car. I still have the notebook with all my "data" and handrawn outlines of a mid60s Mopar intermediate. I think writing this comment is the first time I've gotten any benefit(?) from all that "research". Thanks. All hail
After watching the video again and thinking about my experiment with the tubing and furnace draft gauge I remember thinking that if I placed a duct from the high pressure area inside the rear wheelwells(a partially skirted design on my Belvedere not entirely unlike on your Jagla) that exited in the low pressure area at the base of the rear window(again, not unlike your British pile) I might see a usefull decrease in drag. I don't know if there's room in the "trunk" of your Jag to run some 6" flexihose from inside the rear fenders to some lovingly crafted gaping slots at the bottom of the window but there might be an increase in range to be had if those areas have similar static pressure relationships as my old Plymouth. I think you should try it since the Belvedere I have now is too nice to take a sawzall to unless someone else has some success hacking thier car car first. Please advise me of any results from testing you may do. Again, all hail
I thought you might have said the only thing the experiment indicated might be helpful was to slow down to 55 in order to avoid all those speeding tickets!
@@GrantOakes HA! Driving since 1981, 3 speeding tickets, none in a hotrod or other fast car, none since my 40th birthday in 2004. I'm very carefull and very lucky apparantly. That Belvedere could eventually pull .89g, 13sec. 1/4s and 19mpg with a 440(just not at the same time)
Your intro regarding confidence in aerodynamics applies to just about anything complicated: Cyber security, data analytics, AI, environmental science, etc. I find that entertaining
It's like having your highschool diploma and you feel like you know how everything works. Then college happens and every day you learn something new, you start to understand how little you actually know.
Yes, but it is particularly applicable where the field is real, not artificially defined. We don't fully understand how the real world (including aerodynamics) works, but we created cyber security, so it is fundamentally more understandable to us.
AI is easy, all you have to do is programme something vastly more intelligent than you, that understands what you want it to do implicitly, and is aware of all the moral/social/financial constraints that you find relevant and wish it to adhere to... Simple, what could possibly go wrong?
An extremely interesting video. I have a friend who, after servicing his CBR, found that it would run perfectly at low speeds but lose all engine power above 80-100 km/h. After taking apart and cleaning the fuel system to no avail, he gave up. Some time later, he saw another stripped-down CBR somewhere, and noticed a piece of rubber that was missing on his bike. Turns out that without that piece of rubber, air that flowed into the fairing at the front at high speeds would affect the air pressure in the carbs or airbox. "Automotive aerodynamics is difficult because there are a lot of complex shapes and a lot of moving parts." -- This reminded me of a book on motorcycle engineering that I read once. That section boiled down to "we just don't know so pick a drag coefficient and roll with it". Cars are relatively predictable since the shape stays at least somewhat consistent, put a flailing human that makes up a quarter to a third of the total weight and all that goes out of the window. Since bikes don't have windows [citation neeeded], this is not an issue.
About NACA ducts: they are only made for high-throughput airflow, NOT for static pressurization as is what you want for a ram air for the intake of jet or other engine. They work well for that for which they were designed, and static pressure is NOT it. If you need static pressure, you use a scoop or other forward-facing inlet that is preferably located in clean air, such as the front of the car or a scoop well above the boundary layer.
The tire thing hit me hard. I went from 18x8 tires to 19x10.5/11 staggered on my mustang and my mpgs on trips from California to Texas went from 30.9 to 27.5 at 71mph
Part of the issue is you're not just adding aero drag, you're almost certainly adding weight, and adding it as rotating mass. If your wheels weigh an extra 10 pounds, you're literally adding a 10 pound flywheel you have to spin up every time you accelerate.
@@5thearth I was maintaining a constant speed 95% of the trips, I would say the weight added to it, but it wasn’t from accelerating, just the added rotating mass sucked up some power, but the big rollers under the car definitely made a aero difference too. It went from 245mm with to 305mm in the back
you'll love this story: My engineering teacher in flight school was once a part of a team designing a new kind of wing. it had a dip or groove of some kind in the middle of the beam that produced a laminar bubble. it would have let planes fly with much less drag. only one problem, which apparently took them years to find out. when it gets wet it stops working. and sometimes in real life, water falls from the sky.
I remember a high school co2 car competition over 20m where someone by accident designed something like this. It was very much not aerodynamic, like you would look at it and go, yep, not aerodynamic. It was super boxy, rough, full of random pits, protrusions, etc... part of the "aesthetic". However, at high speed all of that stuff introduced a bubble that dramatically, and I mean dramatically reduced drag. It was shocking. The thing would always, and I mean always win. By several car lengths most of the time. Making a design like was suggested in the video couldn't beat it. Beating it took replicating the design and then smoothing as much stuff out as you could without disturbing that bubble. Only then would that car get beaten, though not by much. Aerodynamics is quite complicated for sure. You change something which should work according to the principle behind it only for it to create MORE drag.
2:33 "it all just trickles down bro" 16:50 This video is unironically really good, including exceptions nicely and explaining things in a way that makes you understand and the humour, sometimes subtle, sometimes not so much...
First off, maaannnn, Matt: I always absolutely love your deadpan humor and delivery. It gets me everytime. Second: All of this footage of Bonneville makes me sad. I moved to SLC for 2.5 years, but both years I lived there, the salt flats were too wet to run (and I had to leave before the third one ran) so I never got to go. Still though, I love getting this insight. Thank you!
I enjoyed this clip a lot! I am a crew member for the BUB 7 motorcycle streamliner. The shape of the streamliner almost directly mirrors that of a Coho Salmon. When tested at the W2 wind tunnel in N. Carolina it was found to have Drag Coefficient of .08. This motorcycle once held the FIM World record with a two-way average speed of 367.382 . We are gearing up to go to the Bonneville Motorcycle Speed Trials on August 27th -Sept1st 2022. We will be testing a newly built Monocoque body as well as new rider Trev Richter. New subscriber and looking forward to more great content!
I'm glad that i found your channel, i'm learning more about understanding things in general on the point where my default answer changed from "yes/no" to "Maybe, idk really, oh might aswell try ". Thank you 😂
One other trick to keep airflow attached is to blow pressurized air from a grid of small holes in the airfoil, that was popular for a while for aircraft flaps. The problem is that when the engine quits, the blown flaps quit with it leading to an extra problem on top of an already hairy situation.
That's me too. This guy is intelligent but not outwardly full of himself. He knows that he doesn't know everything and so keeps an open mind about new info. He takes that info and tests it, not just explaining a gut feeling.
I am a huge fan of your channel, I just want to leave you some love. Thanks for making your videos incredibly entertaining and educational. It’s like a perfect balance with pacing and your presentation style is really fun. I really appreciate your work!
I learned a lot about aerodynamics following the human powered vehicle (HPV) records in Battle Mountain, Nevada. Aerodynamics seems easy to those who know very little. "Oh, just make it a teardrop shape", but the aerodynamicists will always say that the results are surprising and sometimes much less predictable. The fastest bikes don't resemble teardrops, especially with the constraints of trying to fit the rider inside them.
beyond simple geometric shapes, the math quickly devolves into "well, let's have a computer handle this part", but you gotta know what you're doing, otherwise it's going to always be 'garbage in, garbage out'
Your channel has the unique effect that even for the subjects that I'm not sure how much interest I have at the beginning, I always end up watching all of your videos through to the end, and I'm glad that I did. Feeling informed, with a smile. I know that I may be kidding myself, as I will probably forget most of the facts (and all of the numbers) in less than a day. But that's OK, because it is entertaining. 🧐😊
Studying for my Aerodynamics exam tomorrow. After a long day decide to relax a bit on youtube. What am i gonna watch? You are correct, an aerodynamics video.
Tip for the Jag Add one of those luggage racks that you see on similar old cars , position it so that the top rail can hold what will effectively be a spoiler that will duct the air in the direction you want. You could just fit a spoiler but it would look out of place . A trick with aerodynamics is to get the turbulence that would normally cause drag to work for you by deliberately making in happen where it can do something useful like feed the engine or cause a low pressure area under the vehicle. The down force that causes the least drag is obtained by creating a low pressure area under the vehicle.
This is pretty much the extent I remember from my one aerodynamics lesson at university 15 years ago. Now my 6 year old son is into drawing cars and keeps asking if this and that are aerodynamic, and I can only answer "yes, but not how you think." I'll have to show him this vid to confuse even more.
I was looking for drag reduction about wheel some time ago, and came across a Volvo research paper that mentioned how letting the brake intake air jet out from the center of the wheel (hub) helps reducing drag by disrupting turbulence around
NACA ducts are almost universally applied incorrectly. They are specifically designed to preserve laminar flow past the opening to reduce skin friction drag downstream of the inlet. They are not designed for maximum pressure recovery. People often use them for engine air intakes, and for radiator inlets, bot require maximum pressure recovery for optimum performance. A Naca duct recovers somewhere in the range of ~ 60% pressure vs 85% of a plain tube facing forward vs 96% for a well designed supersonic inlet, and 98% for a commercial subsonic aircraft engine inlet.
@@tinolino58 tell that to F1 teams during the NA era. You have to shape the internal volume properly, but you can get more mass into the engine with it done properly. But they have much different drag/downforce priorities, so what remains to be seen is if the drag tradeoff is worth it on an LSR car.
When using ram air induction remember to tune your engine to handle that extra air to get any benefit. You could also use a tool to monitor your engines computer (if it has one) and watch your manifold pressure to see if that goes up at speed to see if it’s working.
@@pchris I'm sorry if I'm rude. This is the simplest question of all. - any modern engine has basic sensor that solves everything you worried (older measured pressure, now - mass or booth). - any old engine solves everything by having carburator. - any racer modifies the firmware. so it's too basic to talk about))) btw, Matt modified Tesla
All hail the algorithm. John Britten ducted high pressure air from the front of his bike to the radiator under the seat for the max DP that he could get and he successfully used a radiator half the size that everyone else was. The drag reduction was impressive. I highly recommend reading what you can about his engineering methods. Also I highly recommend reading "Doing More With Less" by Paul Ciotti for the same reasons. Edit: The title of the book is actually "More with less: Paul MacCready and the Dream of Efficient Flight" ( ISBN-10: 1893554902 )
@@farnarkleboy My apologies, I tried a couple of times to reply to your comment but they were getting removed. I edited my original post. Maybe this will work.
My best example for how unsure we are about aerodynamics is that some guy put a spoiler on and started getting better mileage. People were saying he was an idiot, probably had tail wind or some other thing was causing it because spoiler causes drag. Nowadays, we know very well spoilers can be used to reduce drag but it still does depend on the car, a speed record car probably won't benefit.
About the engine intake from the front : (a) some race teams tape over eg cooling ducts for qualifying laps because this reduces drag. I vaguely recall someone saying because it reduces effective wetted area, orthogonal to any change in airflow over the rest on the car (b) in a previous video you mentioned you thought there would be a be a gain despite the losses from the pipe back to the engine by just letting the inlet pressurise the entire inside of the car removing the need for the duct would have less losses. But viewed another way a much higher wetter area but much lower flow rate. So who knows. But it will cool the driver a bit and help fan the flames backwards if the engine catches fire. Testing. The opposite if the same question .. where will you dump the exhaust, out the side, top bottom or at the back ?
It would be different from a cooling duct because the engine would be actively pumping air, rather than adding restriction like a heat exchanger. I’ll have the exhaust going out the back.
While pressurized cabin would possibly ‘fan’ the flames rearward, adding oxygen via fresh air source will make any open flame hotter and more destructive.
@@SuperfastMatt So you'll purposfully make the opening small enough so the air is sucked faster than it's ramed? you don't want any reverse flow there i'd asume... also the engine intake will create pressure waves possibly screwing it all up... argh too many variables, just test it and tell us thanks :D
@@SuperfastMatt why not duct the high pressure nose directly to the tail? Or feed it into an airpump driven off driveline PTO? All clean air of course. Exhaust is best thrusting out the rear
@@SuperfastMatt There are papers suggesting that using the exhaust for slot-blowing might usefully reduce skin drag... is that type of thing allowed on your car? Formula 1 had those blown diffusers for a while that relied on a similar idea. Awesome videos, thanks!
The transition from aerodynamics to bio mechanics is incrementally subtle.. You are seriously gifted for presenting complicated concepts, understandably while entertaining..
At Bonneville you have 2, yes only 2 miles to get up to speed. Then you have 3 one mile timed sections. The section you go fastest in is what counts. then you have about 3 miles to get stopped.
I designed a vehicle as per your specifications at @17:08, great design! However, I was cleaning it with a fine shammy the other day and all the sudden it started to leak turn signal fluid out of the front nosecone. Then it wouldn't start at all for like 30 minutes afterwards! Do you have any advice?
Gotta say... I don't know that I'd fully discount the aero work that was done 50 years ago. After all, they did produce the SR-71 and other extraordinary aircraft using that same imperical methodology.
@@383mazda It's true--- but that's only true to a point though, because that battle becomes exponential; after a certain speed, it takes twice the power just to go 2% faster, and then twice the power again, just to go 1% faster. At certain speeds, drag bursts you into flames-- think of a meteor coming into the atmosphere at 39k MPH. Drag ultimately wins the battle against power increase. lol..
Tear drop is old school, Around the 70' Laminar flow bodies were discovered. They have significantly lower drag, but zero downforce, that's why they are used for the HPV land speed record, underwater autonomous vehicles and low drag aircraft.
The engineers of your 1950's Jaguar knew a LOT about aerodynamics and drag, they did the C and D types, after all, using only scale wind tunnels and visual observations
Didn't Jaguar stick hundreds of 3" lengths of wool all over the bodywork? If the wool stayed straight against the body work, those areas were considered to be good aerodynamically whereas the areas where it fluttered would need more work (turbulent flow).
What you said in the beginning about how the more you learn about aerodynamics the less certain you are about it seems to apply to a lot of engineering on account of the close relationship it has to physics. I noticed the same thing with electrical engineering. When you learn the engineering side of things, everything's all idealized and simplified so you can learn the basics. Then you get into the physics side of things and learn that everything you were taught under engineering was wrong and dumbed down and this is how it really works. Which is much less than idealized and as a result, a lot more complicated and more difficult to analyze accurately. I think this was actually one of the first things Feynman addressed in his lecture series. Sort of. That when you first start learning physics, everything's idealized and simplified until you understand the fundamental material, then you get into the real world stuff and learn that none of the math you learned is accurate at all and that no matter how hard you try, you can never get it perfectly accurate, anyways. But in most contexts, it's good enough. In others, you can always shoot for the highest precision reasonable.
The wildest thing I learned about aerodynamics in the past year-ish is how unbelievably UN-aerodynamic motorcycles are. To a fucking bike, they're all worse than a full size truck from the 80's. This is why my KLR, while it had a favorable power/weight ratio for around-town hooliganery, flat out could not pass a car at 70 MPH.
Motorcycle aero design is a pain in the ass, the wheels are proportionatly much bigger and rotating whels are hard to analyse, you have to acount for the position of the rider and lugage and you need someting that's much more stable than a car (undesrtandig instabilitys and variable flow direction as in a curve is realy dificult). I think that that'sthe reason they intruduced aero devices in moto gp just recently
@@dnlvrl. on my Goldwing there is a big difference just from taking the trunk off. Over 80mph with the trunk on you can feel the turbulence. At 115 it's scary. Without the trunk it's more stable and can hit 120mph. Found a shorter than stock windscreen, about 4 inches, makes a difference if you tuck in behind it at higher speeds.
5:24 There's slight error. The decrease in mileage is not caused by drag, it is caused the nature of bigger wheels itself. The bigger the wheels the more power needed to run it.
I could endlessly watch videos just like this one. I look forward to more like this. Especially the ones that educate people on how *little* they actually know.
Thanks for not conflating fast with quick. Traditionally of course, you just made your vehicle light, and put the most powerful possible engine in it. Aerodynamics was what you had to resort to when your car wasn't fast enough!
As hydro and aerodynamic engineer at marine industry, I could not agree more with you. Salesmen and managers keep demanding answers to issues that I just cannot give at conference room. "Why can't you promise that we'll have perfect wind shelter in the back seat of bow rider..." when the boat can move anything between 20 to 50 mph, can have wind from any direction, can have a trim of 1 to 4 degrees, people sitting there may be anything from 4 to 6 ft... Like open top vehicles' turbulent airflow was easy to manage even before.
You sound newbie when you start apologizing for unable to include a subtopic, but you gracefully explained the important points of aerodynamics. my goodness, you explain better than me and my teachers in science.
As a pilot it feels funny when car guys talk about laminar airflow and vortex generators and attached flow and Cd etc. Matt: shape your car to become widerband higher further back to gain laminar surface. Check the reynold numbers. Use some Wool thread at the car body to find the station for the vortex generators.. have fun.
Thank you very much, I’m curious about the bow wake generator, I’m a Chevy guy, however, the taurus you showed, is certainly capable of setting records, nothing is faster than a rental car. 😺
I feel like the most cost efficient (and fun) way to simulate aerodynamics is to 3d print a model and put it in a homemade laminar flow box for a wind tunnel. The wind tunnel can be made of scraps and the 3d printer costs like 200 bucks. compared to absurd software costs, this is great! And while it won't calculate pressures and super high speeds for you, you walk away with an actual holdable 3d physical model.
Unfortunately, wind-tunnel testing is tricky for land vehicles because to get accurate results the ground needs to be moving at the same speed as the air. You can get somewhat-reasonable results with a fixed ground surface in a wind tunnel, but you really need to pay a fair bit of attention to not having a large boundary layer on top of it that affects the flow around the model, and you can't really see the effects of anything near the ground.
9:02 (Regarding tail fins) "An airfoil shape will give the car a correcting moment with a lot less drag." This is also very true of model rocket fins. The Apogee Components web site claims a 75% drag reduction from simply rounding the leading & trailing edges, and an additional 85% reduction from a carefully designed airfoil shape.
Looking forward to watching this later. Aerodynamics is what's holding back my Harley from breaking 120 mph. Owned a Sportster and currently a Dyna and a VFR. Despite my Dyna having a lot more torque and accelerating quicker than my old Sportster was a little faster, got to 125 but my Dyna barely reaches 120. Then my VFR with about 1/3 the torque can reach 155. All on flat ground. I'm confident it's all down to aerodynamics.
Impeccable shaftsmanship at the end there, solid 10/10. The video was pretty good too.
Convergent evolution.
'shaftsmanship'. Colour me impressed with your phallic terminology.
I wasn't sure if I was gonna sub to this channel before, but seeing that in the end, there was no question anymore. Every good video has at least one badly 'disguised' knob in it.
10/10
@@alkestos it might be because I'm in America and I don't hear it much but I think knob is my favourite slang wourd for a phallus... 🤣...
The faster, harder and longer you want to ram through the air or any fluid the closer you get to the most efficient ramming shape there is...
Just discovered this guy and he's the first RUclips car guy I've seen caveat literally every idea for car aerodynamics. When he introduced who NACA was instead of just saying a NACA duct sucks in air, I knew he's the real deal.
My neighbour is nearing 90 years old, he's an aero engineer who has consulted extensively since his retirement in his mid 70s. He's sharp as a tack and still gets calls from DoD colleagues when they are stuck. I was stunned when he told me about some of his colleagues in the 1950s joking about their previous work... "Ze guidance has to be so accurate now, my last boss vas happy as long as ve hit London"
"my last boss" lol and theyre german, hilarious
was his name Dr Strangelove?
@@thedude4795 en.m.wikipedia.org/wiki/Operation_Paperclip#:~:text=Operation%20Paperclip%20was%20a%20secret,Europe%2C%20between%201945%20and%201959.
what an awesome story lol, was it actually von braun or just another of the german minds we stole?
since it was (as i recall) more than 80 german and austrian high profile scientists and engineers back then, probably.
Von Braun died in the 70s as i remember 😅
And we just start building inflatable space stations. He would be so bored.
@@NEprimo He never met Von Braun as far as I know
I burst out laughting everytime you showed Kermit flailing his arms around to display turbulent flow. This is one of the best, most visual descriptions I've head and I'm going to use it from now on!
17:00 if you're in the UK the custom is to attach a small bell at the front to get a sense for how much the air is flowing, this also helps you remember which end is the front. It's the bellend.
Very cool - I didn't know that!
@@meatcreap wooosh
They say some people are innately qualified to be employed as the measuring device instead of the bell. Unfortunately for them, it seems to coincide with having not exactly stellar character traits.
I have a bell on my motorcycle but it's to ward off road gremlins, nothing to do with aero.
@@__Razer this is a joke bellend is a insult
The Dodge Charger Daytona and Plymouth Superbird, Chrysler's NASCAR homologation efforts around 1970 used textured vinyl on their roofs. This served two purposes, first the rough texture did have a "golf ball" effect which helped stabilize a shape that was never designed to go 200 MPH. And second and perhaps more importantly, it covered the slapdash bodywork done to the 2500 street versions they had to try to sell. NASCAR banned vinyl tops for 1971.
I'm wholly impressed by how you wrapped up a very serious dissertation on aerodynamics with a dick joke.
Thanks, I was worried it was just my sick mind.
@@craigleemehan That, too, of course. But who's counting?
You're new here aren't you..
@calholli who cares
@@danielclaudio5764 He does dick jokes all the time--- that was my point. Thanks for caring.
I’ve watched probably 100+ aero videos, and this is hands-down my favorite, ever.
Thank you for that.
Same :)
Everyone always asks if I ever took an aerodynamics class in engineering school. Of course I tell them I did, but the class was not whatever they imagine aerodynamics to be. It is a dark art, with understanding inversely proportional to knowledge.
Good to know! My dumb a$$ would have shown up with a calculator and not a goat for sacrifice. lol
As a senior engineer of a wind tunnel for a major automotive OEM, I can confirm. Since I've been doing this job for 11 years, I'm regularly labeled "aerodynamicist" which is a term I hate. It implies that I know something about aero, but most of my job consists of me saying, "who knows? Let's just test it to find out."
I did take aerodynamics in engineering school. It's remarkable how much of the earlier course work focuses on "these are the general ways that these idealized perfect shapes act in a perfect airflow that has no entropy or flow separation". The later course work is focused on "And this is a simplified view of how the real world makes all of that stuff weird and not as usable as we led you to believe". Even worked for a brief spell at a wind tunnel, where it turns out that even the advanced coursework's simplified real world stuff we learned was only a little bit helpful, especially as you get further from idealized conditions.
Thank you , as an armchair aereodynamicist who just enjoys learning about aircrafts i was always stunned when things i learned where contradicted later on ,
So ye , i should probably get a real hobby
It's good to know that all fields of engineering have "that one branch" which is all a black art; I still recall when I first started to understand how RF circuits worked in theory and went "Aha!" and then realized that actually building them was a completely different thing...
The transition from aerodynamics to bio mechanics is incrementally subtle.
Probably one of those things that is significantly different between hydrodynamics and aerodynamics, but one of the things we have found in racing sailboats is that a slick, glossy hull surface is often slightly less performant than a sanded, matte surface. Something about the roughened finish wetting, making the dominant interaction be water on water instead of water on fibreglass.
The Olympic Soling class used this to great advantage; you could tell pretty quickly who sanded their hulls and who polished them. The sanded hulls were usually a boatlength or two ahead consistently.
Surface tension in hydrodynamics is very different than the surface tension in aerodynamics... Well, different probably isn't the right word but the forces are vastly different in strength.
The same interaction between hull and water is interesting in that the object is to reduce the wetted area of the hull to reduce friction . On powerboats air is ducted in from the chines located at the steps to induce a carpet of bubbles that the wetted surface is in contact with . On sail boats where regs do not permit such devices , the introduction of a rough surface creates microbubbles of air which unstick the wetted area . On WLSRs you are actually trying to make the boat fly but keep contact with the water . Compared to air ,water is a high viscosity fluid which causes plenty drag . Renato "Sonny" Levi was the first to recognise this creating the Levi Delta common in most planing hulls sometimes combined with a conical form to create the ' conical delta' hulls .
In an inlet port with a mixture of fuel and air a polished finish produces poorer flow and less bhp than a port finished with 60 grit cones to maintain good turbulence by mini vortices and attachment to port walls . Its good to polish the exhaust as a) the exhaust gas is forced out and b) it delays build up of fouling .
Although the fluid difference is very significant, the same effect does occur in air. I think it is worth examining whether laminar or turbulent flow is idea for different areas of the body.
That's the reason why you don't polish the intake/s of your engine.
Comparing water and air is closer than it would appear when the velocities are high. Air gets VERY hard to push through and if you start to apply serious power to something it's going to heat up. Wonder if a pressurized boundary layer type skin wouldn't help with the friction losses. Maybe only need the pressurized (or even suction) panels here and there to really clean up the profile.
I was thinking about the golf ball aerodynamics all along the video. Never saw the Mythbuster episode but I saw a research video on golf ball aerodynamics that compared even dimples vs random size and distribution of dimples. Very happy that you saw the question coming.
I'm beginning to think every car Matt works on needs to have a hidden phallus somewhere.
'Hidden'
@@josephssen Well, the dry sump tank phalli in the Honda are pretty effectively hidden.
One could argue that the LSR car itself is one giant phallus 😆
After reading up on theory and (tested) examples on an ecomodding website, I made some aero mods to my 2005 Accord to reduce its drag (for fuel efficiency reasons, not speed).
I did A-B-A-B testing during relatively stable weather. Runs in both directions, straight level road, no traffic, using cruise control with the car left on for consistent speed.
Short airdam w/ curved lip connected to a partial undertray under the engine bay, partial grille block, side mirrors folded back. Could add/remove all at the side of the road with simple tools.
Got ~4.25% fuel efficiency improvement at 55mph. Pretty happy with that.
Remember when some cars came from the factory without passenger mirrors?
About 20yrs ago I cut up 200 ft of 1/4 clear vinyl tubing and ran it from inside my 66 Belvedere hardtop to points all over the body. Base of the windshield, grill, fenderwells, area behind rear window, and like that. Then I had my buddy Sam drive me around on I-81 at 80mph while I hooked up each tube to a furnace exhaust stack vacuum gauge and wrote all the results down. My plan was to figure out where the high and low pressure areas were so I could see if there was any way to duct the high pressure air to the low pressure areas to reduce drag or make it rain behind the car or something. The only thing the experiment indicated might be helpful was to remove all the glass from the car. I still have the notebook with all my "data" and handrawn outlines of a mid60s Mopar intermediate. I think writing this comment is the first time I've gotten any benefit(?) from all that "research". Thanks. All hail
Very cool guerrilla engineering.
After watching the video again and thinking about my experiment with the tubing and furnace draft gauge I remember thinking that if I placed a duct from the high pressure area inside the rear wheelwells(a partially skirted design on my Belvedere not entirely unlike on your Jagla) that exited in the low pressure area at the base of the rear window(again, not unlike your British pile) I might see a usefull decrease in drag. I don't know if there's room in the "trunk" of your Jag to run some 6" flexihose from inside the rear fenders to some lovingly crafted gaping slots at the bottom of the window but there might be an increase in range to be had if those areas have similar static pressure relationships as my old Plymouth. I think you should try it since the Belvedere I have now is too nice to take a sawzall to unless someone else has some success hacking thier car car first. Please advise me of any results from testing you may do. Again, all hail
I thought you might have said the only thing the experiment indicated might be helpful was to slow down to 55 in order to avoid all those speeding tickets!
@@GrantOakes HA! Driving since 1981, 3 speeding tickets, none in a hotrod or other fast car, none since my 40th birthday in 2004. I'm very carefull and very lucky apparantly. That Belvedere could eventually pull .89g, 13sec. 1/4s and 19mpg with a 440(just not at the same time)
@@jonathangehman4005 I had a 64 Belvedere with a 426 wedge, 3.91 gears and could pull 6" wheelies. That was perhaps the fastest car I ever owned.
Your intro regarding confidence in aerodynamics applies to just about anything complicated: Cyber security, data analytics, AI, environmental science, etc.
I find that entertaining
It's like having your highschool diploma and you feel like you know how everything works. Then college happens and every day you learn something new, you start to understand how little you actually know.
Yes, but it is particularly applicable where the field is real, not artificially defined. We don't fully understand how the real world (including aerodynamics) works, but we created cyber security, so it is fundamentally more understandable to us.
In retail, we call it under-promise and over-deliver. lol
AI is easy, all you have to do is programme something vastly more intelligent than you, that understands what you want it to do implicitly, and is aware of all the moral/social/financial constraints that you find relevant and wish it to adhere to... Simple, what could possibly go wrong?
You say that with a high level of confidence….
An extremely interesting video.
I have a friend who, after servicing his CBR, found that it would run perfectly at low speeds but lose all engine power above 80-100 km/h. After taking apart and cleaning the fuel system to no avail, he gave up. Some time later, he saw another stripped-down CBR somewhere, and noticed a piece of rubber that was missing on his bike. Turns out that without that piece of rubber, air that flowed into the fairing at the front at high speeds would affect the air pressure in the carbs or airbox.
"Automotive aerodynamics is difficult because there are a lot of complex shapes and a lot of moving parts." -- This reminded me of a book on motorcycle engineering that I read once. That section boiled down to "we just don't know so pick a drag coefficient and roll with it". Cars are relatively predictable since the shape stays at least somewhat consistent, put a flailing human that makes up a quarter to a third of the total weight and all that goes out of the window.
Since bikes don't have windows [citation neeeded], this is not an issue.
That diagram at the end made my Monday, thanks Matt 🤣🤣
Are you watching this from the future?
About NACA ducts: they are only made for high-throughput airflow, NOT for static pressurization as is what you want for a ram air for the intake of jet or other engine. They work well for that for which they were designed, and static pressure is NOT it. If you need static pressure, you use a scoop or other forward-facing inlet that is preferably located in clean air, such as the front of the car or a scoop well above the boundary layer.
I fucking love this channel! From beginning to thankful ending. It's always just the best from Matt.
The tire thing hit me hard. I went from 18x8 tires to 19x10.5/11 staggered on my mustang and my mpgs on trips from California to Texas went from 30.9 to 27.5 at 71mph
Part of the issue is you're not just adding aero drag, you're almost certainly adding weight, and adding it as rotating mass. If your wheels weigh an extra 10 pounds, you're literally adding a 10 pound flywheel you have to spin up every time you accelerate.
@@5thearth I was maintaining a constant speed 95% of the trips, I would say the weight added to it, but it wasn’t from accelerating, just the added rotating mass sucked up some power, but the big rollers under the car definitely made a aero difference too. It went from 245mm with to 305mm in the back
I enjoyed the longer video immensely but I have this weird feeling that I actually learned something. I'm sure it will pass.
you'll love this story:
My engineering teacher in flight school was once a part of a team designing a new kind of wing. it had a dip or groove of some kind in the middle of the beam that produced a laminar bubble. it would have let planes fly with much less drag.
only one problem, which apparently took them years to find out.
when it gets wet it stops working.
and sometimes in real life, water falls from the sky.
I remember a high school co2 car competition over 20m where someone by accident designed something like this. It was very much not aerodynamic, like you would look at it and go, yep, not aerodynamic. It was super boxy, rough, full of random pits, protrusions, etc... part of the "aesthetic". However, at high speed all of that stuff introduced a bubble that dramatically, and I mean dramatically reduced drag. It was shocking. The thing would always, and I mean always win. By several car lengths most of the time. Making a design like was suggested in the video couldn't beat it. Beating it took replicating the design and then smoothing as much stuff out as you could without disturbing that bubble. Only then would that car get beaten, though not by much.
Aerodynamics is quite complicated for sure. You change something which should work according to the principle behind it only for it to create MORE drag.
Sounds like a Klein-Fogelman airfoil.
Engineering humour is rarest humour . . . . next to accounting humour. Also, drag is caused by exposure to feather boas, sequins and stage makeup.
Economist humor might be rarer....until you know that most of the field is performance art.
@@jimiverson3085 Economics is really just Philosophy vs Religion.
You are seriously gifted for presenting complicated concepts, understandably while entertaining.
So glad we never have to experience childish humour on this channel.
Cheers mate. 🍻😁👍
Yeah.. only adult humor.
I dont know.
The is a well educated idiot, painfully boring to listen to.
But that would be your wavelength.
@@calholli Wasn't the concept of adulthood as we understand in current culture just a social construct?
Hell yeah, dad jokes all the way 😂
2:33 "it all just trickles down bro"
16:50 This video is unironically really good, including exceptions nicely and explaining things in a way that makes you understand and the humour, sometimes subtle, sometimes not so much...
First off, maaannnn, Matt: I always absolutely love your deadpan humor and delivery. It gets me everytime.
Second: All of this footage of Bonneville makes me sad. I moved to SLC for 2.5 years, but both years I lived there, the salt flats were too wet to run (and I had to leave before the third one ran) so I never got to go. Still though, I love getting this insight. Thank you!
I enjoyed this clip a lot! I am a crew member for the BUB 7 motorcycle streamliner. The shape of the streamliner almost directly mirrors that of a Coho Salmon. When tested at the W2 wind tunnel in N. Carolina it was found to have Drag Coefficient of .08. This motorcycle once held the FIM World record with a two-way average speed of 367.382 . We are gearing up to go to the Bonneville Motorcycle Speed Trials on August 27th -Sept1st 2022. We will be testing a newly built Monocoque body as well as new rider Trev Richter. New subscriber and looking forward to more great content!
I'm glad that i found your channel, i'm learning more about understanding things in general on the point where my default answer changed from "yes/no" to "Maybe, idk really, oh might aswell try ". Thank you 😂
One other trick to keep airflow attached is to blow pressurized air from a grid of small holes in the airfoil, that was popular for a while for aircraft flaps. The problem is that when the engine quits, the blown flaps quit with it leading to an extra problem on top of an already hairy situation.
Your drawing shows that nature knows the answer to everything.
It’s the fastest shape. Mine can go from 0 to 100 back to 0 in just a few seconds.
Size does matter in aerodynamics.
@@calholli Size always matters, my friend.
When Kelly Johnson was designing the YF-12/SR-71 he had a sign hanging in the design shop; "NO BUMPS". Works for speed record cars also.
I love your content, you’re one of the only content creators I have the bell on for.
Same
That's me too. This guy is intelligent but not outwardly full of himself. He knows that he doesn't know everything and so keeps an open mind about new info. He takes that info and tests it, not just explaining a gut feeling.
Me top, great humour
Same!
I am a huge fan of your channel, I just want to leave you some love. Thanks for making your videos incredibly entertaining and educational. It’s like a perfect balance with pacing and your presentation style is really fun. I really appreciate your work!
Tamper throwing toddler takes tons of torque! Totally true! :D
I learned a lot about aerodynamics following the human powered vehicle (HPV) records in Battle Mountain, Nevada. Aerodynamics seems easy to those who know very little. "Oh, just make it a teardrop shape", but the aerodynamicists will always say that the results are surprising and sometimes much less predictable. The fastest bikes don't resemble teardrops, especially with the constraints of trying to fit the rider inside them.
This feels like it addressed everything I ever cared to know about aerodynamics minus all the math. great video!
beyond simple geometric shapes, the math quickly devolves into "well, let's have a computer handle this part", but you gotta know what you're doing, otherwise it's going to always be 'garbage in, garbage out'
That's like learning everything there is to know about a woman without touching her.
@@calholli For some women, I think thats preferable.
What about internal aerodynamics?
But he didn't even touch on what happens when you approach and surpass the speed of sound. Don't tell me that doesn't make you curious.
Thanks for explaining the golf ball dimple thing. That helped.
Your channel has the unique effect that even for the subjects that I'm not sure how much interest I have at the beginning, I always end up watching all of your videos through to the end, and I'm glad that I did. Feeling informed, with a smile. I know that I may be kidding myself, as I will probably forget most of the facts (and all of the numbers) in less than a day. But that's OK, because it is entertaining. 🧐😊
Studying for my Aerodynamics exam tomorrow. After a long day decide to relax a bit on youtube. What am i gonna watch? You are correct, an aerodynamics video.
Tip for the Jag
Add one of those luggage racks that you see on similar old cars , position it so that the top rail can hold what will effectively be a spoiler that will duct the air in the direction you want.
You could just fit a spoiler but it would look out of place .
A trick with aerodynamics is to get the turbulence that would normally cause drag to work for you by deliberately making in happen where it can do something useful like feed the engine or cause a low pressure area under the vehicle.
The down force that causes the least drag is obtained by creating a low pressure area under the vehicle.
I think something at the back of the roof made to look like one of those old sunshades people would fit above windscreens could work.
@@Jonathan_Doe_ . Possibly better than my idea but far more obvious and probably a lot uglier in the execution.
@@Jonathan_Doe_ Why am I now thinking about the Ford Sierra Cosworth. That I recall had a subtle extension at the back of the roof.
@@XenonJohnD Very subtle, and it also doubled as a handy ironing board.
Thanks for summing up with the illustration at 17:11, nature is actually good at reducing drag
This is pretty much the extent I remember from my one aerodynamics lesson at university 15 years ago. Now my 6 year old son is into drawing cars and keeps asking if this and that are aerodynamic, and I can only answer "yes, but not how you think."
I'll have to show him this vid to confuse even more.
Nice prank bro.. it's only his future we're talking about
I love you. J.s. such complexity to enjoy there.
I was looking for drag reduction about wheel some time ago, and came across a Volvo research paper that mentioned how letting the brake intake air jet out from the center of the wheel (hub) helps reducing drag by disrupting turbulence around
I love the baby and the panicked Kermit the Frog for unhappy airflow! (Former Aerodynamics Engineer here) I also love the MythBusters reference!
I was literally going to ask about NACA ducts, and that's when the segment started! Awesome information without melting the brain!
NACA ducts are almost universally applied incorrectly.
They are specifically designed to preserve laminar flow past the opening to reduce skin friction drag downstream of the inlet.
They are not designed for maximum pressure recovery. People often use them for engine air intakes, and for radiator inlets, bot require maximum pressure recovery for optimum performance. A Naca duct recovers somewhere in the range of ~ 60% pressure vs 85% of a plain tube facing forward vs 96% for a well designed supersonic inlet, and 98% for a commercial subsonic aircraft engine inlet.
I'm really interested to see your real-world ram air test results! Great video, thank you.
Ram air doesn’t work. High speed air has no pressure and it doesnt feed any engine or cooling system well.
Ram air looks cool. Thats all!
@@tinolino58 tell that to F1 teams during the NA era. You have to shape the internal volume properly, but you can get more mass into the engine with it done properly. But they have much different drag/downforce priorities, so what remains to be seen is if the drag tradeoff is worth it on an LSR car.
@@jsquared1013 in airplanes we build a difusor to regsin airpresure and slow down turbulence
I was thinking about dimples and myth busters the whole episode! It was satisfying to see it at the end. Excellent as always!
When using ram air induction remember to tune your engine to handle that extra air to get any benefit. You could also use a tool to monitor your engines computer (if it has one) and watch your manifold pressure to see if that goes up at speed to see if it’s working.
A gm mass airflow sensor could do both of those things.
@@k20nutz assuming the engine doesn’t already have one of its own
lol. let's invent EFI
@@Ritefita the engine may already have efi. I don’t know what he’s using other than that it’s a Honda motor bike engine
@@pchris
I'm sorry if I'm rude.
This is the simplest question of all.
- any modern engine has basic sensor that solves everything you worried (older measured pressure, now - mass or booth).
- any old engine solves everything by having carburator.
- any racer modifies the firmware.
so
it's too basic to talk about)))
btw, Matt modified Tesla
All hail the algorithm.
John Britten ducted high pressure air from the front of his bike to the radiator under the seat for the max DP that he could get and he successfully used a radiator half the size that everyone else was. The drag reduction was impressive. I highly recommend reading what you can about his engineering methods. Also I highly recommend reading "Doing More With Less" by Paul Ciotti for the same reasons.
Edit: The title of the book is actually "More with less: Paul MacCready and the Dream of Efficient Flight" ( ISBN-10: 1893554902 )
I tried searching for "Doing More With Less" by Paul Ciot, but can't find anything . Do you have an ISDN for it or a publisher ?
@@farnarkleboy it is 'More With Less'
@@farnarkleboy My apologies, I tried a couple of times to reply to your comment but they were getting removed. I edited my original post. Maybe this will work.
@@p.t.anderson1593 Thanks , got it , much appreciated
My best example for how unsure we are about aerodynamics is that some guy put a spoiler on and started getting better mileage.
People were saying he was an idiot, probably had tail wind or some other thing was causing it because spoiler causes drag.
Nowadays, we know very well spoilers can be used to reduce drag but it still does depend on the car, a speed record car probably won't benefit.
About the engine intake from the front : (a) some race teams tape over eg cooling ducts for qualifying laps because this reduces drag. I vaguely recall someone saying because it reduces effective wetted area, orthogonal to any change in airflow over the rest on the car (b) in a previous video you mentioned you thought there would be a be a gain despite the losses from the pipe back to the engine by just letting the inlet pressurise the entire inside of the car removing the need for the duct would have less losses. But viewed another way a much higher wetter area but much lower flow rate. So who knows. But it will cool the driver a bit and help fan the flames backwards if the engine catches fire. Testing. The opposite if the same question .. where will you dump the exhaust, out the side, top bottom or at the back ?
It would be different from a cooling duct because the engine would be actively pumping air, rather than adding restriction like a heat exchanger. I’ll have the exhaust going out the back.
While pressurized cabin would possibly ‘fan’ the flames rearward, adding oxygen via fresh air source will make any open flame hotter and more destructive.
@@SuperfastMatt So you'll purposfully make the opening small enough so the air is sucked faster than it's ramed? you don't want any reverse flow there i'd asume... also the engine intake will create pressure waves possibly screwing it all up... argh too many variables, just test it and tell us thanks :D
@@SuperfastMatt why not duct the high pressure nose directly to the tail? Or feed it into an airpump driven off driveline PTO?
All clean air of course. Exhaust is best thrusting out the rear
@@SuperfastMatt There are papers suggesting that using the exhaust for slot-blowing might usefully reduce skin drag... is that type of thing allowed on your car? Formula 1 had those blown diffusers for a while that relied on a similar idea. Awesome videos, thanks!
The last sketch was my favorite. Summed it all up nicely i think.
🤣 Thanks for going over shapes and dimples. Very great content here. Aerodynamics are definitely complicated and very interesting!
The transition from aerodynamics to bio mechanics is incrementally subtle.. You are seriously gifted for presenting complicated concepts, understandably while entertaining..
Yay ! Welcome back !
At Bonneville you have 2, yes only 2 miles to get up to speed. Then you have 3 one mile timed sections. The section you go fastest in is what counts. then you have about 3 miles to get stopped.
i see Matt, i click. i am a simple schnitzl.
Didn't even read the title before clicking, I have time to do that while the ads play
This is my first video of yours. All hail the algorithm.
I just hope the rest of what you have is as good.
Please keep up the great work
I designed a vehicle as per your specifications at @17:08, great design! However, I was cleaning it with a fine shammy the other day and all the sudden it started to leak turn signal fluid out of the front nosecone. Then it wouldn't start at all for like 30 minutes afterwards! Do you have any advice?
was it crying
Your drawing shows that nature knows the answer to everything.. The transition from aerodynamics to bio mechanics is incrementally subtle..
Gotta say... I don't know that I'd fully discount the aero work that was done 50 years ago. After all, they did produce the SR-71 and other extraordinary aircraft using that same imperical methodology.
when modern data and simulation discount it tho... maybe it's time to move on ;)
@@MogR91 sure, once it's proven and published.
The Russians had the Mig-25.. turns out brute force has a seat at the table.
@@calholli lol, good point. The flip side of the "reduce drag" coin is moar powah!
@@383mazda It's true--- but that's only true to a point though, because that battle becomes exponential; after a certain speed, it takes twice the power just to go 2% faster, and then twice the power again, just to go 1% faster. At certain speeds, drag bursts you into flames-- think of a meteor coming into the atmosphere at 39k MPH. Drag ultimately wins the battle against power increase. lol..
That silence after the "wing it" joke got me! 😂😂😂 cheers for the in depth info 🤙
That closing image was epically hilarious
This is an all time great video. Fantastic information, well laid out, with one of the best outro cards I’ve ever seen 😂
Great video 👍 So would a shark skin texture finish on a vehicle be a good aerodynamic choice in regards to laminar flow ?
I've always wondered this too.
You ever seen a racing shark?
@@sexyfacenation those are the ones with the stripes down the middle
Tear drop is old school, Around the 70' Laminar flow bodies were discovered. They have significantly lower drag, but zero downforce, that's why they are used for the HPV land speed record, underwater autonomous vehicles and low drag aircraft.
"Matt hasn't uploaded in a while"
Google knows.
The engineers of your 1950's Jaguar knew a LOT about aerodynamics and drag, they did the C and D types, after all, using only scale wind tunnels and visual observations
Didn't Jaguar stick hundreds of 3" lengths of wool all over the bodywork? If the wool stayed straight against the body work, those areas were considered to be good aerodynamically whereas the areas where it fluttered would need more work (turbulent flow).
The more you know the less you know... Ahh classic Dunning Kruger effect 🤗 Algorithm 🙋♂️!
What you said in the beginning about how the more you learn about aerodynamics the less certain you are about it seems to apply to a lot of engineering on account of the close relationship it has to physics. I noticed the same thing with electrical engineering. When you learn the engineering side of things, everything's all idealized and simplified so you can learn the basics. Then you get into the physics side of things and learn that everything you were taught under engineering was wrong and dumbed down and this is how it really works. Which is much less than idealized and as a result, a lot more complicated and more difficult to analyze accurately.
I think this was actually one of the first things Feynman addressed in his lecture series. Sort of. That when you first start learning physics, everything's idealized and simplified until you understand the fundamental material, then you get into the real world stuff and learn that none of the math you learned is accurate at all and that no matter how hard you try, you can never get it perfectly accurate, anyways. But in most contexts, it's good enough. In others, you can always shoot for the highest precision reasonable.
The wildest thing I learned about aerodynamics in the past year-ish is how unbelievably UN-aerodynamic motorcycles are. To a fucking bike, they're all worse than a full size truck from the 80's. This is why my KLR, while it had a favorable power/weight ratio for around-town hooliganery, flat out could not pass a car at 70 MPH.
Yet a1984 GL1200 Goldwing with fairing trunk and saddle bags can do 115mph.
The three extra cylinders help. HP torque and gearing help
@@craigwiess1656 Yes. The take-away is motorcycles have seemingly absurd power/weight ratios because they need them.
Motorcycle aero design is a pain in the ass, the wheels are proportionatly much bigger and rotating whels are hard to analyse, you have to acount for the position of the rider and lugage and you need someting that's much more stable than a car (undesrtandig instabilitys and variable flow direction as in a curve is realy dificult). I think that that'sthe reason they intruduced aero devices in moto gp just recently
@@dnlvrl. on my Goldwing there is a big difference just from taking the trunk off.
Over 80mph with the trunk on you can feel the turbulence. At 115 it's scary. Without the trunk it's more stable and can hit 120mph. Found a shorter than stock windscreen, about 4 inches, makes a difference if you tuck in behind it at higher speeds.
5:24 There's slight error. The decrease in mileage is not caused by drag, it is caused the nature of bigger wheels itself. The bigger the wheels the more power needed to run it.
A month later... 💀💀💀
I could endlessly watch videos just like this one. I look forward to more like this. Especially the ones that educate people on how *little* they actually know.
Im glad you touched on the golf ball dimples. I was wondering about that (thanks to mythbusters).
Thanks for not conflating fast with quick.
Traditionally of course, you just made your vehicle light, and put the most powerful possible engine in it.
Aerodynamics was what you had to resort to when your car wasn't fast enough!
Looong aerodynamic shape at the end.. lol. Cheers from Brazil!
Thank you for explaining the golf ball dimples. I was thinking it and what you said made sense.
"All hail the algorithm!"
This is the first video i have watched from this channel and I'm already in live with it, damm your production quality is great
Stimulating convo... It all came together with that brilliant drawing at the end; nice finish.
Your introduction is the most scientific introduction i heard in a long time :-) I wish every scientific thing would be handled like your explanation.
Reducing turbulence... love some of the technology in Aviation!
That outro pic of the red motorcycle powered car is awesome. It should be a poster. I’d buy it.
I'm pretty sure the pic was lifted from when the car was on the Jay Leno's Garage channel.
I love the constant use of pictures of the temper tantrum any time chaos is mentioned LOVE IT hahaha
As hydro and aerodynamic engineer at marine industry, I could not agree more with you. Salesmen and managers keep demanding answers to issues that I just cannot give at conference room. "Why can't you promise that we'll have perfect wind shelter in the back seat of bow rider..." when the boat can move anything between 20 to 50 mph, can have wind from any direction, can have a trim of 1 to 4 degrees, people sitting there may be anything from 4 to 6 ft... Like open top vehicles' turbulent airflow was easy to manage even before.
You sound newbie when you start apologizing for unable to include a subtopic, but you gracefully explained the important points of aerodynamics. my goodness, you explain better than me and my teachers in science.
This is my favorite RUclips channel, every time I see a post I watch the whole thing right away, great stuff 👌👌
@3:43 those exhaust pulses hitting the ground is a cool shot!
As a pilot it feels funny when car guys talk about laminar airflow and vortex generators and attached flow and Cd etc.
Matt: shape your car to become widerband higher further back to gain laminar surface. Check the reynold numbers. Use some Wool thread at the car body to find the station for the vortex generators.. have fun.
Destin from "Smarter Every Day" would agree that laminar flow is the best flow!
Awesome video.
Thank you.
I love your signature at the end. Subscribed. All hail algorithm!
that mythbusters episode... thanks TV Cultura for bring this program in Brazil, that lighted up my science passion!
Wasn't expecting the fancy and precise final design.
Thank you very much,
I’m curious about the bow wake generator,
I’m a Chevy guy, however, the taurus you showed, is certainly capable of setting records, nothing is faster than a rental car. 😺
I feel like the most cost efficient (and fun) way to simulate aerodynamics is to 3d print a model and put it in a homemade laminar flow box for a wind tunnel. The wind tunnel can be made of scraps and the 3d printer costs like 200 bucks. compared to absurd software costs, this is great! And while it won't calculate pressures and super high speeds for you, you walk away with an actual holdable 3d physical model.
Unfortunately, wind-tunnel testing is tricky for land vehicles because to get accurate results the ground needs to be moving at the same speed as the air. You can get somewhat-reasonable results with a fixed ground surface in a wind tunnel, but you really need to pay a fair bit of attention to not having a large boundary layer on top of it that affects the flow around the model, and you can't really see the effects of anything near the ground.
9:02 (Regarding tail fins) "An airfoil shape will give the car a correcting moment with a lot less drag." This is also very true of model rocket fins. The Apogee Components web site claims a 75% drag reduction from simply rounding the leading & trailing edges, and an additional 85% reduction from a carefully designed airfoil shape.
best video about Aerodynamics that I've seen
Looking forward to watching this later. Aerodynamics is what's holding back my Harley from breaking 120 mph. Owned a Sportster and currently a Dyna and a VFR. Despite my Dyna having a lot more torque and accelerating quicker than my old Sportster was a little faster, got to 125 but my Dyna barely reaches 120. Then my VFR with about 1/3 the torque can reach 155. All on flat ground. I'm confident it's all down to aerodynamics.