*IMPORTANT NOTE* There's a lot of confusion about the engine size and how many cylinders are required. While the example I showed is four cylinders, you only need one in the simplest form. You can have any style air compressor beforehand (superchargers are air compressors), and you could have the combustion cylinder simply be larger to increase its expansion ratio. Four-cylinders is a logical way of explaining it, but as far as how the tech can be implemented, you could use 1, 2, 3, 4, however many cylinders you like. Also, both of the last two cylinders do useful work, not just the first combustion cylinder. As it is two-stroke, this will increase energy density relative to a 4-stroke engine design (double the power strokes per RPM).
Could you not just have petrol at a super high pressure + a super high compression ratio ? eg common rail diesel but with petrol? You could inject the petrol very quickly and also activate the spark plug just after
Good explanation as usual. I'll review this again. I'm not overly impressed with the tech though. Look whst Honda got out of the CVCC engine introed in the USA in 1975. Emissions down and power and mileage up. Fixed the teething probs and it was a good model for them. Stratified charge maybe still has some potential with new technology????? Just a thought!
if a supercharger is able boost too such high pressures, will not take enormous amount of energy. Considering length of travel of high pressure air will not lose energy. It would be great if this engine comes out with maintaining present efficiency but it many increase considerable amount of weight not reflecting much on to vehicle implying increase in power density must be such high it compensates this. Your emission also tend increase since your increasing number of cycles of power extraction implying running at low rpm is not worth it since emissions are measured at grams/km. If this engine is able switch between both present and proposed systems at considerably low mid range rpms system has much to gain.
15 years ago I worked in the Student Admissions office of a well known 2 year automotive mechanic trade school. As I was a bit of a motor-head at one time or another I had sat in (audited) every class from auto transmissions to British electrical systems. During this time I came across some very dedicated, very experienced instructors not one came to your level of communitive skills. You ability to explain technology in a way the vast majority of "tender-foots" can understand is a talent. Thank you for the time and effort you put into your channel. Be happy, be safe.
I would love to see how the valves are sealing against the chambers. Extremely high pressure and lateral movement seems like a difficult mechanism to seal properly.
@@jay_321 But in a two stroke there is oil mixed with the fuel to lubricate the sliding parts so more burnt oil in the exhaust, which is not what we want in a four stroke engine when trying to lower emissions in an engine and make it more efficient. The sliding valve idea is good, but keeping it lubricated and cool in a high pressure and temperature environment brings in the reliability issue. Wankle engines are a classic example of this.
It looks like the valves seal themselves. The slide valves are under most pressure during the compression stroke but because the compression stroke is happening elsewhere from the combustion chamber, the pressure is actually forcing the valves against their sealing surfaces. During the power stroke, as far as I can tell, the valves stay open and the built-up pressure in the other chamber is what stops the expanding gas from travelling backwards. The only pressure that's trying to force the valves open is the small amount of exhaust gas that's retained to help ignite the fresh mixture. Of course, that exhaust gas pressure is being opposed by the high-pressure air/fuel mix on the other side of the valve so the net force is still greatly biased toward being applied to the intake side of the valve. Even just smooth metal would seal under that much pressure. It would be interesting to see how they've managed to combat wear though.
No one: Engineer: "I'm going to develope a 2 stroke that's more efficient than a 4 stoke. It's going to have different sized pistons and a slider valve. It's going to be bad ass."
@Tobias modern 2 strokes are much better. The evinrude boat engines produce more power but less emissions than a 4 stroke. No mixing fuel and oil too. There are 2 tanks, the engine regulates the ratio automatically.
@Tobias that's because you burned oil and gas by mixing them for fuel. By design, you are not mixing oil and gas so it has the potential to pollute less by producing more power and using less fuel, theoretically. I think in reality, the slider is going to require lots of oil and that's going to mix with the fuel like it or not and transfer into the cylinder during the pressure balance pre-ignition and by unintended consequence of design, the slider mechanism will be mixing gas and oil anyway and therefore burning it anyway. Plus, look at how close in proximity the fuel ignites past the slider! The bottom of the slider is the top of the combustion area, so the temp will be very high there. Are you going to need a super high viscosity oil to withstand those temps to prevent buildup on the slider! How is the slider going to operate with higher viscosity? With that amount of surface area between the slider plates, wouldn't you want a lower viscosity? There's so many ways for this completely fail outside of solidworks!
@@rustynail914 Actually the oil injector is prone to failure (they've had that for 20 years) if it ever fails your engine will die.... its better to just mix it manually that way you know what is in there for sure. On the other hand if someone borrows your boat and runs it without oil it will also fail!
My first thought: Wait, isn't that a super charger with piston form? My second thought: Wait a minuet, isn't that a turbine jet engine with piston form?
@@DChrls What's that got to do with what he said? His point is that it works using the same thermodynamic principle as a modern turbine engine: several compression stages and several expansion stages.
That was my first thought, it's basically doing the same work as a turbo or super charger. So I guess the issue boils down to cost of production being cheaper?
Came here to say this! Sounds like an attempt to make a piston engine function like a turbine engine with separate compression, combustion, and power-extraction sections. I’m concerned they’re going to acquire losses through added complexity, moving parts, and friction from “turning” the air (in jet engines you try to avoid “turning” the air in cases where you don’t get anything out of it)
I was thinking compound steam engine with the exhaust stages. I never thought of using this idea on the input side. The separation of the input and exhaust stages reminds me of James Watt's improvement to the Newcomen engine. The question that comes to mind here is do you need to have the two stages even connected by one crankshaft? Using two separate crankshafts, or, better to my mind, two separate housings, allows you to construct and run the stages for the benefit of each stage. Would it be easier to use a supercharger for compression or use one in conjunction with the two input compression stages?
@@twoeightythreez we just like the mechanical linkage to our throttle. On my 54 I can throttle where ever I want. Shift wherever I want. My daily doesn't do that. So I like carbs. I never have and never will drive a 100k sports car so I can't speak to their throttle feal
@@zHxIxPxPxIxEz there are cable driven throttle bodies. Have you ever had to re-jet a carb after a cam swap? That is a horrendous experience. Much easier to make a few adjustments on a Holley terminator... everything that’s new is not always bad.
@@2blkSSs I'm not saying new is bad at all. I like full mechanical driving experience. And yeah I've had to tune. Both are fun. For me if I'm driving or working on a car for fun I want old. That's why I have a 1954.
Years ago I saw a RUclips video on an engine concept that used 2 cylinders for combustion. The first cylinder compressed the air and the second burned the fuel. I've frequently wondered if this could be combined with direct inject in the first cylinder for a more efficient 2 stroke engine. This video shows an advanced approach that solves many problems that I had with my ideas. Thanks for the video.
@@MyFabian94 It's fundamentally different because you have a second expansion stroke, that's where the efficiency comes from it uses most of the energy that would go out the exhaust. A split engine still only has one expansion stroke, it's just done by two small pistons instead of a single large one. The split design is only there to guide the flow through and get rid of the exhaust gases as effectively as possible. Fundamentally it's still an otto cycle engine, like every four stroke out there. Still it looks to complicated for mass production with acceptable performance and cost. Many modern engines, especially Diesels, already use some of the exhaust energy via a turbocharger, so the gain in efficiency would probably not be as large as indicated.
I could see this being useful in a plug-in hybrid where this acts as a backup generator. You wouldn't need to worry about variable load in that case, and the efficiency is great for recharging the battery if grid power isn't available. Plus, if the engine doesn't run as much, it makes the long term reliability of the slider value less of an issue, assuming you try to plug in your car more than let it recharge on its own. Bonus points for being quiet.
While the numbers aren't quite as great, the gas turbine could perform similarly efficiently and that is a very well proven technology. This is really cool, but it seems a little ponderous.
I thought the same thing. However, the load would still be variable, but the battery (or other storage system) would act as a sort of "buffer" between the load demand from the electric motors and the engine, it would make it easier to manage and give it more time to react to fast load/unload cycles that driving generates.
Current Corolla takes egr post cat, through a passage in the head, through an egr cooler, then back to the intake manifold. Benefit is the engine warms up 3 times quicker, drawback is if the coolant is low it doesn't cool the head passage or egr cooler, then when coolant does find it's way back, things crack pretty quickly.
this man is amazing I have learned more from this guy than from 40+ years of my life. I worked as a trainee mechanic for 6 months even that didn't teach me as much as this man
If that's the case, and it's quieter while running, it could make for a decent plug-in hybrid system where engine power can be low and constant and the electric motor takes up the normal load changes while driving.
Air cooled engines to this day still do a great job at for generators up to about 700 cc. Honda is a large manufacture of those type gens. I don't see them adding this to a generator due to complexity and engine cost not even in a larger displacemt and higher output gen set. They did do air cooled diesel 5000 W and 12000 W liquid cooled diesel but dropped them years ago for various reasons. Inverter technology improved the generators about 33 years ago as a 1st in production. Fuel injection has been added but that just upped the cost. Conventional gen sets still sell well with A C engines and a stator and rotor VS the alternator on an inverter type.
@@MrAjam12 cost is a big factor producing hybrids. If its too costly they wont do it. If they do it (and some have) depending on the vehicle they loose money and that's not an option now. Even before the virus hit us. Toyota did well but the sold a varient of the same Prius model for years keeping their costs down and profits up. I think hybrids are the way to go for now. Allowing manufacurers to be profitable enough to really develop all electric vehicles properly and profitably. Tesla did ok with his vision but I cant see those vehicles grabbing enough market share just yet. Maybe they should develop a hybrd for the short term and rock the legacy manufacturers into disappearing. For now though pick up trucks and large SUVs are the big 3s salvation until someone can shake those trees down.
@@mooglemy3813 I agree, I think this tech will be too expensive for hybrids. Especially considering how new and just how much investment it will take. I would love to see this go Into a car, but I doubt Toyota will pick this up seeing how conservative they are when it comes to new products. Iirc Tesla partnered with some legacy manufacturer (Toyota or ford, which one escapes me) to help make the batteries for a hybrid. I think Tesla is In a horrible position to make a hybrid. They'd have to buy an engine from some one else and retool a bunch of their plants, something they already are breaking the bank doing. I think their all electric approach is great for them, they can't beat anyone in the gas world so they made their own electric world to be king of. Also the model 3 is the top luxury sendan as of recently iirc
Great explanation, Jason, but I think such engine will never end up in a road vehicle. It seems like it's very efficient, but not so compact and powerful. It might be an efficient generator or something like this, but I really doubt that some automaker will invest millions in that technology while EVs are getting better and better
Ironic Goose since it is two stroke instead of four, it has twice as many power strokes, and the last two cylinders both generate power. Power density should be the same.
You do realize that automakers still invest 10 times more money into petrol/hybrid technology than fully electric technology because petrol engined cars still sell 100 times more
@@rogerfroud300 no they're stick around for atleast another 2 decades if not more, combustion engines still serve more broad practicality especially when it comes to weight to range ratio.
@@broshido2745 Hybrid maybe and even then I doubt it because Toyota has already pretty much perfected it, but some like Daimler(Mercedes) have already announced they won't spend a single € to develop a newer gen of ice engines. The writing is on the wall for those who want to see it.
There is also a pre-chamber ignition method. Used in F1 and LMP cars and finally coming out for a road car with Maserati MC20. It practically eliminates two stage combustion and knock while being a well known and ironed-out technology.
*looks at the amount of moving parts, looks at the concept, looks at the theory* so... a split cycle engine with even more moving parts and even more complex?
Two-stroke engines are by far the simplest and have been displaced from cars many decades ago. Despite their simplicity, cheaper maintenance and never needing an oil change, their inferior efficiency and worse emissions have made them obsolete. Same will happen to other engines that will successively be replaced by electric motors over the next decades. When exactly? Even the experts don't agree, so we'll just have to wait and see.
@@mercury0214 Exactly. The government will have to force combustion engines off the road. Like they are doing in the UK, Europe by driving up the road tax's for diesel and petrol engines. Plus making exhaust emission laws that are almost impossible to meet and maintain.
Yeah, I got a bit hung up with that also but apparently, most of the pressure is used up during the power stroke and the exhaust valve is timed to limit the pressure to not overcome the slider valve. I'm with you, poppet valves have reigned for a long time and the fingers of a slider valve is a very troublesome arrangement with the pressure considered. I recall many decades back experiments being done with 'swing valves' which were mounted more or less like rocker arms with a valve head on the end - it went nowhere apparently, never saw any further examples published.
You can look at WWI plane rotary piston engines such as the French Gnome/Le Rhone to see why mixing/breathing chambers are an incredibly terrible idea as well
@shane turbo-compounding is a great way to decrease mechanical reliability. The ginormous R 4360 engines used on the dc6 and -7 piston airliners had a trio of "power recovery turbines" that the exhaust gasses blew through to power the crankshaft through a clutch. Any mechanic that worked on the engines called the PRTs "parts recovery turbines", they did a huge number on engine reliability. Like needing rebuilds four times as often! 500 hours time between overhauls, when a non turbo compound engine would last 2000hours!
I remember seeing something like this several years ago. They called it "the 5 stroke engine." It was under development around the same time that Duke engine was being developed, and a few other thinking outside the box internal combustion engines.
Not just like. I'm pretty sure the engine's slider will be made with more than $0.04 worth of material and would also have a bearing surface and lubrication.
eventually even the smart people brains will hit the cap and AI will take over inovation, churning new ideas, concepts, engines, optimizations, faster then anyone could. Even allot of theses inovations we see today already are only possible because of new powerfull computers who simulate many projects that would too much work for humans alone to do on a simple pen and paper way.
Internal combustion engines have so much potential! Imagine an engine with HCCI or EI with the electro-pneumatic valve actuation found in the Koenigsegg Gemera.
@@CompTechs It seems like the BSFC of the engine doesn't warrant the cost or repair bills that could possibly exist. In steady state power productions there are much less complex and reliable means of power. In heavy industry there are far superior means of power production. In racing or even mild automotive applications this is so far down on the possible uses that flatheads would be brought back before this was thought about.
this divulged into utter bs, engine development is long complete, but what would yt channels do if it wasn't for mazda and others' silly dreams. that slide valve, how long untill it breaks there? come on....
This reminds me of the creation of the triple expansion tech of steam engines. My (ignorant) immediate reaction is, you appear to have one "firing" cylinder moving four cylinders. To potentially have enough energy (4 cylinder size) to move a car, you would need the engine to have 4X4 = 16 cylinders. Neat video / potential tech, Thanks.
It’s definitely an interesting concept. My main issue (which you actually brought up) is the reliability. Generally more complexity results in a decrease in reliability. I’d rather have a less efficient engine that’ll last forever. In a normal road car at least. Track is a separate conversation.
My problem would be power/weight. As i said above, with this you essentially have a once cylinder engine that's the size of a 4 cylinder, with loads of parasitic loss.
I want to say that I really appreciate your videos. Your content makes up for the other stuff on RUclips. Like the garbage I see children watch on the internet. Please continue to explain things in simply understood ways. You and Practical Engineering are the modern equivalent to the ancient training videos. Basic concepts, straightforward explanations, better educated viewers. We might now be living in 1984 (and have done it to ourselves), but the electric screen has also finally reached its potential as an educator. I salute you for being a part of the solution.
7:57 You said, that the combustion is going to have less pressure, than the initial air-fuel mixture. The initial air-fuel mixture however has less pressure, than it takes the gasoline to ignite. Therfore, the final combustion must have less pressure than just regular gasoline explosions in a usual cilynder. (if a
Traditional engines have high pressure for a short period. This has a lower pressure for a longer period (near constant pressure burn, slow). This increases the area of the pressure-volume diagram, increasing work done.
The compression ratio refers to the difference in volume, not pressure! The effiency is therefore less dependant on a pressure differential, but more so on the difference in volume.
@@EngineeringExplained I thought you wanted to burn all of your fuel as soon and quickly as possible. So you can get as much work out of the expanding gas. Burning fuel when the engine is a few degrees away from bottom gets you much less work than burning the same amount of fuel at the top of your stroke
@@EngineeringExplained yeah, but "work done" isn't the metric. Efficiency is impossible unless nearly all of the fuel's energy is converted to heat/pressure during dwell. After dwell the only issue should be "clean up", which MUST be largely done relatively early in expansion because otherwise the "clean up energy" is wasted. It's not like any system harvesting energy from a catalytic converter will be more than a few percent efficient.
There's only compressed air mixed with fuel there. How would that build up soot? The fuel burns as it enters the "power" cylinder. Nothing burns in the reservoir, nor do any exhaust gases go there. Fuel is also good at cleaning stuff, such as valves in engines that have fuel injectors in the throttle body. So it's the opposite of soot build-up. Probably the cleanest part of the engine.
@@Kepe I understand that part of the design. However, you'd notice that fuel burn occurs during the opening of the valves and it will inevitably cause some burnt gasses to seep through the "high pressure" reservoir. Though the point you made with fuel being a cleaner does make sense, we've still seen examples of injectors clog up despite them supposedly having high pressure fuel sprayed out of them. Of course, the difference is that injectors are inside the combustion chamber as opposed to this design. The only point I'm trying to make is that those valves seem like the weak link in this design, really. Especially due to its "sliding" design as opposed to a cork-like seal found in traditional ICE. I guess only time will tell how well this engine fares.
@@Kepe soot came from chemicals used in Petrol additives and also in storage tanks, that's why 4stroke engine is made to eradicate all of that issue, if own a two stroke engine you know how this engine will fail eventually
@@Kepe soot came from chemicals used in Petrol additives and also in storage tanks, that's why 4stroke engine is made to eradicate all of that issue, if own a two stroke engine you know how this engine will fail eventually
Since the reservoir is higher pressure than the combustion chamber, soot would not be able to back flow in there. They use the same concept for operating theaters. The operating room is kept at a higher pressure than the outside rooms so airborn dust cant float in. If anything, you would have to worry about leakage from reservoir to combustion mid cycle. Then again the combustion chamber MUST be at a higher pressure than the reservoir during combustion. Otherwise you wouldn't need combustion and could just run off the reservoir pressures. If the seals leak you could get some back flow there.
I've been watching you for a couple years now. No I have not accidentally started my own online work training's with "Hello, and welcome." and concluding with "If you have any questions or comments, please feel free to leave them below." Great stuff as always good sir!
Interesting how things come around and go around. I'm glad to see someone trying to use the principals of the 1906 Compound and the Honda CVCC . Probably never find high hp, but there should be efficiency in there somewhere.
Sometimes where theory meets practice, the water muddies. Those old Honda CVCC engines would carbon up the tiny intake port for the prechamber, and the things would run terrible until you pulled the choke out (thankfully they had manual chokes!) and richened the mixture into the main cylinder. Of course, that killed fuel mileage and the HC emissions went off the scale, but at least it would get you where you’re going ...
If you draw a jet engine next to the entry ignition engine, they look pretty much same. The first piston is like the low pressure compressor stages on a jet engine, the second piston is just like high pressure compressor stages, the mixing chamber is sort of but not really like the combustion chamber on a jet engine, the third piston is like the high pressure turbine stages, and the fourth piston is like the low pressure turbine stages. The only difference is that pistons are in the place of compressor and turbine blades and unlike a jet engine, entry ignition doesn't undergo continuous combustion.
This does seem like a lot of moving parts, and since rotary valves make a lot more sense but have never caught on, I'm not too encouraged about the slider valve. Side question: has anyone tried just using the exhaust rotor of a turbo to generate electricity in a hybrid? Seems like a simpler way to leverage exhaust pressure/heat, and who cares about lag time?
What about packaging? You’re taking up the space of a 4 cylinder with only one of the pistons doing the work (granted 2 stroke vs 4 stroke), but still...
I imagine this engine is focused on efficiency, with power a far second, or third. Most people are perfectly fine with 200hp, which this should reach, as it's forced induction
For high efficiency I could see a two strock diesel, multi-stage turbos and direct injection allowing a 30 to 50 compression ratio. The turbo would be coupled with the crankshaft by a planetary gear box acting as a supercharger/turboprop. So the pistons would take care of the high pressure and no lag tork response and the inlet turbos would take care of the low pressure compression (1 to 10 atm.) and cool it with an intercooler before sending it to the cylinder head. The exhaust turbo would contribute to the engine tork (like a turboprop engine) and keep the combustion gas at higher pressure for a longer time allowing a more efficient burn and therefore creating cleaner imitions. This way you also remove the exaust cam friction and double the amount of cylinder heads combustion for the same amount of internal friction.
There was a British engine in the 1980s that never went beyond prototype. It had a small primary air cylinder where rich mixture was mixed and ignited. The part-burnt gas exhausted into the main cylinder containing hot compressed air where the burn completed. It was clean and efficient.
I remember seeing a local interview with the guy that patanted this. He was going to license the technology to Toyota but then never heard anything since then.
Wow. This makes a hell of a lot of sense. I was wondering how F1 would go to a 2 Stroke engine in the future after these V6 Turbo Hybrids. This explains it I guess. 👌
I can only imagine how much space this would take to operate, regardlessof how many "cylinders" it possesses, since fewer cylinders means more attachments to precompress the air. Thinking of that slider valve, I imagine you could determine how wide it opens to act as a throttle control, but really electronically controlling the amount of fuel injected would help with that. Now how thick would those slider valve plates have to be to resist the heat and pressure of that combustion chamber? And how would it be lubricated to prevent siezing as the metal expands when heated? And carbon buildup could very well prevent it from working. Might be good for an alternative low carbon fuel though! Pretty cool idea though!
In the 1970s Honda had their carbureted CVCC Engine in the civic. It had a divided combustion process where the main part of the cylinder was lean and a much smaller thimble shaped pocket in the head with a rich charge that was spark ignited and blew into the main cylinder like a torch increasing efficiency and lowering emissions to the point that it didn't need a catalytic converter.
@Engineering Explained 3:40 we can control the ignition timing by changing the compression level . i mean there can be something like extra isolated valves (air in the combustion chamber cant move behind that valve) on the cylinder head to move up and down by just some millimeters to adjust the compression level in the combustion chamber . so by increasing the compression level earlier it can ignite earlier than normal.
After being completely amazed, the first thought I had was "but how does it start?" almost two years later I'm still left wondering... "How does it start?" But it's still super cool...
one quick question: how do u make the first combustion when starting the car? from my understanding u need combustion to generate heat then heat leads to another combustion, but before starting there is no heat.
@@hopsgarage5513 If compression is high enough you don't need to... at 20:1 compression you almost don't need glow plugs and Detroit 2 strokes don't' have them (they get an air charge from a blower + compress that then boom all without plugs and as long as the engine isn't worn out they start up in a jiffy at above freezing temps and you can start them below freezing with some extra turning over as you mentioned). My 3-53 detroit will pretty much fire up on the first revolution.
@@Wingnut353 having high compression doesn't mean quick starting, Nor does it mean no glow plugs. The blower on a 53,71 or 92 series is to clear the cylinders of exhaust and provides little performance gains hence the turbo addition later. Sure there are some quick starting diesel but I've never seen any start in one revolution.
Notionally very interesting, but it reminds me of many attempts to optimize various machines that become so complex that either mechanical reliability or manufacturing cost or maintenance, etc. overwhelms any efficiencies gained. In grad school, I went out to sea with a student who had built a high-resolution sonar array similar to a phased-array radar. Great idea, great resolution - on land, or in a tank. At sea, with rolling ship, waves crashing about, the entire spider web was impossible to deploy and maintain as a planar transducer array. The practical overwhelmed the theoretical advantages. I would love to see an experimental test bed of this form of IC engine that was tunable and measurable, from which to derive some costs and complexity data. It might well lead to a simplification path that would be even more effective. Interesting tutorial, as always.
I've been mulling over, for some time, the idea of one cylinder pressurising a working cylinder. Somehow I never managed to think it all through so it was a revelation to watch this video. Incidentally it seems to me that, in a standard otto cycle engine, using an exhaust driven turbo-charger is a good idea because it uses the not inconsiderable energy still present in the expanding gas when the exhaust valve opens. I also think that the turbo should be kept spinning at some minimum speed by an electric motor-generator as in an F1 ERS system. In a road car, at higher revs when the turbo is being spun at sufficient speed by the exhaust gas, the motor-generator could be switch to generation thus making a separate alternator un-necessary.
Lubricating that slider would prove to be a nightmare. The only way this could be done would be to use castor oil, which poses another set of problems. Also, the efficiency of this scheme would seem to be less due to greater internal friction. And this would be a very expensive engine to build; With electric cars on the horizon, I doubt any auto company would want to spend the money to go down this route. Great video!
Intake/exhaust poppet valves are not lubricated in the combustion chamber. Mostly up/down motion, but they also can rotate. Fair point though, as described the slider mechanism would be challenging to lubricate.
@@EngineeringExplained My original design used an I/O valve that combined a poppet (to handle pressure) and a way low pressure rotating gate. The engineer I talked to from Volvo's SuperTruck engine development team said that going with such a system would take a decade and a huge amount of money to bring to market, and there'd be no guarantees. It's not like a company is going to put untested stuff into a product that, if it proves to not be durable, would sink the company. So those guys will have to do all the development on their own time and dime. This alone just about guarantees that the engine you described will not come to market (unless your name is Bezos). So, by the time a single engine was sold the patent would be close to expiring. Not a good bet. And, not contradicting you, just adding my two cents, poppet valves are adequately lubricated for rotational movement because the stem is lubricated, there's no rotation when they're closed, and when they're open the valve and its seat don't touch.
Improving international combustion engines is important. But they did improve some emissions like diesel with diesel exhaust fluid. Could you do a video of how diesel exhaust fluid works?
When the fuel is sprayed into the mixing chamber, it will ignite and expand into the pressure reservoir and mixing chamber first. When the slider valve opens up, then the expanding pressure from the burning air/fuel will start pushing down on the third cylinder. So, the volume of the pressure reservoir and mixing chamber become part of the third cylinder's volume.
ornately over-complicated. An opposed piston system with the intake valves in the pistons using a roots to pressurize the crankcase would beat it any day of the week.
Besides improving the combustion engine, what if we use all possible energy like also recovering the heat generated by the engine (and usually vented by the radiator) for an external combustion engine like a Stirling engine, build that setup with hybrid battery pack and profit? Combustion engine linked to wheels via clutch + cvt, stirling engine only generating current, electrical engines on the wheels and the chance to disengage the combustion engine via the clutch to run on full electricity if we have enough charge in the batteries. OFC I said Stirling engine because it is the first that comes into my mind, but in its place you can put the most efficient external combustion engine you can think about, with size considerations regarding how much heat it can utilize.
Another noteworthy benefit is a convenient capture point for high pressure bleed air. There are a lot of possibilities such as: pneumatic start (via the same port as the capture point), bleed air operated HVAC blower, air suspension, seat cooling, electronics cooling, external compressed air utility hookup.
I can also give another drawbacks, which is the main challenge of displacing an engine properly. It is quite difficult to arrange between engine configs, such as Inline-4 (shown), Inline-6, V6, V8, etc.
I can skip most of your sliding etc by adding a turbo down stream from the carburetor/injector as a heater/mixer to raise the pressure and the temp or the incoming charge. The air fuel mixing is done in the intake tract. You can dump the extra cylinder and accomplish the same thing.
While NOT for road applications, a triple expansion steam engine with Corliss valve gear is QUITE efficient. The overall efficiency "gotcha" that's never discussed with internal combustion engines of any sort is the amount of energy consumed in preparing the fuel for use. "The perversity of the Universe tends towards a maximum." The molecular structure of distilled crude oil has abominably bad anti-knock properties, for both the gasoline (octane #) and diesel (cetane #) fractions. Energy is expended to alter that undesirable structure into something whose anti-knock properties is OK. ANYTHING that burns, regardless of molecular structure, can be used to generate and superheat steam. Of course, the combustion process must not be a significant polluter. Lunch is NEVER truly free.
A diesel often burns oil when it goes runaway. The other cause would be a fuel leak inside the cylinder. It is very difficult to stop in an automatic transmission. But in a manual it's just as easy as stalling the engine.
it happens when an engine oil (too much of it) finds it's way into the combustion chamber. Either sucked in with the air through a leaky turbo or simply through a crack in the block or head (I think). Since a diesel engine can run on oil, cutting of the fuel pump or a battery won't do you any good, because it sustains itself by pulling more oil in and doesn't require a spark to run. If that happens, your best bet is to stop the car, stay on the brake, put in the highest gear and quickly release the clutch, which should stall it out. If you have an automatic, you could try to plug the air intake with whatever you can find. However, modern diesels have a throttle body that should close when you turn of the ignition, starving it of oxygen :-)
My wifes 2017 Hyundai has the 2.0 Atkinson engine. It does well for efficiency if you drive it with that in mind. 37 to 40 Hwy MPG the 6 speed gives it plenty of pep down low. Very happy with it vs the direct injected alternatives
Reminds me of the "twingle" two stroke engine on a Puch motorcycle. The rear cylinder contained the crankcase transfer ports, and the front cylinder had the exhaust ports. The head covered both cylinders with a common combustion chamber.
Seems to work like a tripple expansion steam engine from 100 yeara ago. Carbon build up will be fun on the slider valves. Would like to see a running version.
Daniel Bryant Reminded me of the movie "To Kill A Mockingbird" as Acticus is leaving the courtroom. They stand and the man tells the boy to stand, "A great man is passing..."
It's somewhat a mix of many ancient tech. The hot air reservoir is basically how hot bulb engine works, and two expansion pistons is the regular compound steam engine principle. Sliding valves are also not new at all. Again, steam engine uses large sliding valves, and rotating sleeve valves were a (oil-greedy) thing of early performance automobiles.
Jason, would it make sense to change two things? 1.) Use an electric supercharger instead of pistons. Have the supercharger's battery be charged by the work done by the engine, which should be greater than the force to bring in air at a given pressure. 2.) Use a pressure valve, instead of a slider valve. Given a high enough pressure, the force of air in the upper chamber should overcome the force of the spring keeping a valve closed, pushing open a valve.
*IMPORTANT NOTE* There's a lot of confusion about the engine size and how many cylinders are required. While the example I showed is four cylinders, you only need one in the simplest form. You can have any style air compressor beforehand (superchargers are air compressors), and you could have the combustion cylinder simply be larger to increase its expansion ratio. Four-cylinders is a logical way of explaining it, but as far as how the tech can be implemented, you could use 1, 2, 3, 4, however many cylinders you like. Also, both of the last two cylinders do useful work, not just the first combustion cylinder. As it is two-stroke, this will increase energy density relative to a 4-stroke engine design (double the power strokes per RPM).
this is basically a turbine but with pistons, you can make the same with compounding a few turbochargers on a two stroke engine
Could you not just have petrol at a super high pressure + a super high compression ratio ? eg common rail diesel but with petrol?
You could inject the petrol very quickly and also activate the spark plug just after
𝕀 𝕒𝕞 𝕥𝕙𝕚𝕟𝕜𝕚𝕟𝕘 ... ℝ𝕠𝕥𝕒𝕣𝕪 𝕖𝕟𝕘𝕚𝕟𝕖𝕤 𝕨𝕠𝕦𝕝𝕕 𝕕𝕠 𝕥𝕙𝕚𝕤 𝕖𝕧𝕖𝕟 𝕓𝕖𝕥𝕥𝕖𝕣
Good explanation as usual. I'll review this again. I'm not overly impressed with the tech though. Look whst Honda got out of the CVCC engine introed in the USA in 1975. Emissions down and power and mileage up. Fixed the teething probs and it was a good model for them. Stratified charge maybe still has some potential with new technology????? Just a thought!
if a supercharger is able boost too such high pressures, will not take enormous amount of energy. Considering length of travel of high pressure air will not lose energy. It would be great if this engine comes out with maintaining present efficiency but it many increase considerable amount of weight not reflecting much on to vehicle implying increase in power density must be such high it compensates this. Your emission also tend increase since your increasing number of cycles of power extraction implying running at low rpm is not worth it since emissions are measured at grams/km. If this engine is able switch between both present and proposed systems at considerably low mid range rpms system has much to gain.
Ridiculous idea, if I've got to use my fingers to control the air going in to the engine, how am I going to drive the car?
I must say I'm rather surprised Jason didn't spot this rather obvious flaw. Maybe he's not as smart as he likes to make out?
elaborate
@@zyadhq8672 wow
Trolling and sarcasm are not generally welcome in the comments of educational discussions.
😂
Rotary engine: My spinning dorito blew 3 gaskets before 80k miles.
EI Engine: Hold my Slider valve...
That design has the problem of having combustion take place in one area.
9k rpm
oh lord ahahahh
@@johnspecht72 The Wankel is obsolete because they have weak seals and horrible efficiency.
Sander Van der Kammen just horrible efficiency, apex seals are way better now.
15 years ago I worked in the Student Admissions office of a well known 2 year automotive mechanic trade school. As I was a bit of a motor-head at one time or another I had sat in (audited) every class from auto transmissions to British electrical systems. During this time I came across some very dedicated, very experienced instructors not one came to your level of communitive skills. You ability to explain technology in a way the vast majority of "tender-foots" can understand is a talent.
Thank you for the time and effort you put into your channel. Be happy, be safe.
I would love to see how the valves are sealing against the chambers. Extremely high pressure and lateral movement seems like a difficult mechanism to seal properly.
seems like valves on a camshaft would've done the trick
rotary valves have been used on 2-strokes effectively. Even piston-port 2-strokes use lateral movement to seal off the combustion chamber.
Seems like those 'slider valves' would get gummed up quickly
@@jay_321 But in a two stroke there is oil mixed with the fuel to lubricate the sliding parts so more burnt oil in the exhaust, which is not what we want in a four stroke engine when trying to lower emissions in an engine and make it more efficient. The sliding valve idea is good, but keeping it lubricated and cool in a high pressure and temperature environment brings in the reliability issue. Wankle engines are a classic example of this.
It looks like the valves seal themselves. The slide valves are under most pressure during the compression stroke but because the compression stroke is happening elsewhere from the combustion chamber, the pressure is actually forcing the valves against their sealing surfaces. During the power stroke, as far as I can tell, the valves stay open and the built-up pressure in the other chamber is what stops the expanding gas from travelling backwards. The only pressure that's trying to force the valves open is the small amount of exhaust gas that's retained to help ignite the fresh mixture. Of course, that exhaust gas pressure is being opposed by the high-pressure air/fuel mix on the other side of the valve so the net force is still greatly biased toward being applied to the intake side of the valve. Even just smooth metal would seal under that much pressure. It would be interesting to see how they've managed to combat wear though.
No one:
Engineer: "I'm going to develope a 2 stroke that's more efficient than a 4 stoke. It's going to have different sized pistons and a slider valve. It's going to be bad ass."
Yet this iteration describesca secondary burn chamber which would draw down the pollution prior the venting to exhaust system.
@Tobias modern 2 strokes are much better. The evinrude boat engines produce more power but less emissions than a 4 stroke. No mixing fuel and oil too. There are 2 tanks, the engine regulates the ratio automatically.
Tobias New TPI engines are euro 4
@Tobias that's because you burned oil and gas by mixing them for fuel. By design, you are not mixing oil and gas so it has the potential to pollute less by producing more power and using less fuel, theoretically. I think in reality, the slider is going to require lots of oil and that's going to mix with the fuel like it or not and transfer into the cylinder during the pressure balance pre-ignition and by unintended consequence of design, the slider mechanism will be mixing gas and oil anyway and therefore burning it anyway. Plus, look at how close in proximity the fuel ignites past the slider! The bottom of the slider is the top of the combustion area, so the temp will be very high there. Are you going to need a super high viscosity oil to withstand those temps to prevent buildup on the slider! How is the slider going to operate with higher viscosity? With that amount of surface area between the slider plates, wouldn't you want a lower viscosity? There's so many ways for this completely fail outside of solidworks!
@@rustynail914 Actually the oil injector is prone to failure (they've had that for 20 years) if it ever fails your engine will die.... its better to just mix it manually that way you know what is in there for sure. On the other hand if someone borrows your boat and runs it without oil it will also fail!
My first thought: Wait, isn't that a super charger with piston form?
My second thought: Wait a minuet, isn't that a turbine jet engine with piston form?
Doesn't have to be a slider valve. They could use a rotary valve or something else.
@@DChrls What's that got to do with what he said?
His point is that it works using the same thermodynamic principle as a modern turbine engine: several compression stages and several expansion stages.
Glad I’m not the only one who thought these
That was my first thought, it's basically doing the same work as a turbo or super charger. So I guess the issue boils down to cost of production being cheaper?
Or a steam engine with combustion chambers, yes/no?
Just not complicated enough for my liking.
If it can be explained on a white board with only 4 colors, I’m with you. Seems too simple ha
PapaWheelie ha funny
IMPRACTICAL EXCERSIZE IN ENGINEERING ... Piled Higher and Deeper production
Rudolph would deem it less practical than his peanut oil engine...
Give it to the Germans, they will find a way to complicate it at least 100% more
That's one the draw backs...complecity,more. That might break
Reminds me of the old steamship engine with high, medium, and low pressure pistons to extract as much energy from the steam as practical.
It really does, his drawings remember me from the Titanic engine animation
Exactly my thoughts. I remember that scene from "Massive engines with Chris Barrie" - Ships episode
Yeah, that is exactly what it is.
Bam! You nailed it.
expansion engine
Air compressor, jet combustor and a steam engine had some fun and tada!!
Seems more like a jet engine in piston form
Came here to say this! Sounds like an attempt to make a piston engine function like a turbine engine with separate compression, combustion, and power-extraction sections. I’m concerned they’re going to acquire losses through added complexity, moving parts, and friction from “turning” the air (in jet engines you try to avoid “turning” the air in cases where you don’t get anything out of it)
@@KdetJim Jason did say "Brayton cycle" which is the jet engine mode of operation, too bad he didn't elaborate as you just have.
I was thinking compound steam engine with the exhaust stages. I never thought of using this idea on the input side.
The separation of the input and exhaust stages reminds me of James Watt's improvement to the Newcomen engine. The question that comes to mind here is do you need to have the two stages even connected by one crankshaft? Using two separate crankshafts, or, better to my mind, two separate housings, allows you to construct and run the stages for the benefit of each stage.
Would it be easier to use a supercharger for compression or use one in conjunction with the two input compression stages?
Yeah it's basically a pulse jet with check valve intake
Now I know how old-school carb guys feel about the computer tuning cars use nowadays.
Except i just don't get how the old school carb guys act as if MPFI is some "newfangled" tech when its been around in most cars for nearly 40 years
@@twoeightythreez we just like the mechanical linkage to our throttle.
On my 54 I can throttle where ever I want. Shift wherever I want. My daily doesn't do that. So I like carbs.
I never have and never will drive a 100k sports car so I can't speak to their throttle feal
I feel like this is more along the lines of going from steam engines to gasoline haha... completely different.
@@zHxIxPxPxIxEz there are cable driven throttle bodies. Have you ever had to re-jet a carb after a cam swap? That is a horrendous experience. Much easier to make a few adjustments on a Holley terminator... everything that’s new is not always bad.
@@2blkSSs I'm not saying new is bad at all.
I like full mechanical driving experience. And yeah I've had to tune.
Both are fun. For me if I'm driving or working on a car for fun I want old.
That's why I have a 1954.
Years ago I saw a RUclips video on an engine concept that used 2 cylinders for combustion. The first cylinder compressed the air and the second burned the fuel. I've frequently wondered if this could be combined with direct inject in the first cylinder for a more efficient 2 stroke engine. This video shows an advanced approach that solves many problems that I had with my ideas. Thanks for the video.
The Two-stroke engine:
"You couldn't live with your own failure. Where did that bring you? Back to me."
I basically see an NSU Split Single with Valves instead of Ports.
a Perfectly Balanced joke
I understood that reference!
@@MyFabian94 It's fundamentally different because you have a second expansion stroke, that's where the efficiency comes from it uses most of the energy that would go out the exhaust.
A split engine still only has one expansion stroke, it's just done by two small pistons instead of a single large one. The split design is only there to guide the flow through and get rid of the exhaust gases as effectively as possible. Fundamentally it's still an otto cycle engine, like every four stroke out there.
Still it looks to complicated for mass production with acceptable performance and cost. Many modern engines, especially Diesels, already use some of the exhaust energy via a turbocharger, so the gain in efficiency would probably not be as large as indicated.
2 stroke without sparkplug?
I could see this being useful in a plug-in hybrid where this acts as a backup generator. You wouldn't need to worry about variable load in that case, and the efficiency is great for recharging the battery if grid power isn't available. Plus, if the engine doesn't run as much, it makes the long term reliability of the slider value less of an issue, assuming you try to plug in your car more than let it recharge on its own. Bonus points for being quiet.
I So agree!!
Hybrids are great! Never have to worry too much about range and you get the awesome efficiency of electric motors.
Going to have terrible maintenance requirements, though. Looking like BMW v8s, "after 50k miles rebuild or replace the engine".
While the numbers aren't quite as great, the gas turbine could perform similarly efficiently and that is a very well proven technology. This is really cool, but it seems a little ponderous.
I thought the same thing. However, the load would still be variable, but the battery (or other storage system) would act as a sort of "buffer" between the load demand from the electric motors and the engine, it would make it easier to manage and give it more time to react to fast load/unload cycles that driving generates.
I’m not an engineer or any thing like that just a car enthusiast but it seems exspensive and hard to repair
complicated designs can be refined and simplified with enough development. Id imagine that early four stroke engines were unreliable as well.
Current Corolla takes egr post cat, through a passage in the head, through an egr cooler, then back to the intake manifold. Benefit is the engine warms up 3 times quicker, drawback is if the coolant is low it doesn't cool the head passage or egr cooler, then when coolant does find it's way back, things crack pretty quickly.
this man is amazing
I have learned more from this guy than from 40+ years of my life. I worked as a trainee mechanic for 6 months even that didn't teach me as much as this man
If your statement is true, I feel very sorry for you.
Sounds like it would be good for constant state applications...perhaps generators?
If that's the case, and it's quieter while running, it could make for a decent plug-in hybrid system where engine power can be low and constant and the electric motor takes up the normal load changes while driving.
Air cooled engines to this day still do a great job at for generators up to about 700 cc. Honda is a large manufacture of those type gens. I don't see them adding this to a generator due to complexity and engine cost not even in a larger displacemt and higher output gen set. They did do air cooled diesel 5000 W and 12000 W liquid cooled diesel but dropped them years ago for various reasons. Inverter technology improved the generators about 33 years ago as a 1st in production. Fuel injection has been added but that just upped the cost. Conventional gen sets still sell well with A C engines and a stator and rotor VS the alternator on an inverter type.
Hybrids, would probably be a perfect application
@@MrAjam12 cost is a big factor producing hybrids. If its too costly they wont do it. If they do it (and some have) depending on the vehicle they loose money and that's not an option now. Even before the virus hit us. Toyota did well but the sold a varient of the same Prius model for years keeping their costs down and profits up. I think hybrids are the way to go for now. Allowing manufacurers to be profitable enough to really develop all electric vehicles properly and profitably.
Tesla did ok with his vision but I cant see those vehicles grabbing enough market share just yet. Maybe they should develop a hybrd for the short term and rock the legacy manufacturers into disappearing. For now though pick up trucks and large SUVs are the big 3s salvation until someone can shake those trees down.
@@mooglemy3813 I agree, I think this tech will be too expensive for hybrids. Especially considering how new and just how much investment it will take. I would love to see this go Into a car, but I doubt Toyota will pick this up seeing how conservative they are when it comes to new products.
Iirc Tesla partnered with some legacy manufacturer (Toyota or ford, which one escapes me) to help make the batteries for a hybrid. I think Tesla is In a horrible position to make a hybrid. They'd have to buy an engine from some one else and retool a bunch of their plants, something they already are breaking the bank doing. I think their all electric approach is great for them, they can't beat anyone in the gas world so they made their own electric world to be king of. Also the model 3 is the top luxury sendan as of recently iirc
Great explanation, Jason, but I think such engine will never end up in a road vehicle. It seems like it's very efficient, but not so compact and powerful. It might be an efficient generator or something like this, but I really doubt that some automaker will invest millions in that technology while EVs are getting better and better
Ironic Goose since it is two stroke instead of four, it has twice as many power strokes, and the last two cylinders both generate power. Power density should be the same.
You do realize that automakers still invest 10 times more money into petrol/hybrid technology than fully electric technology because petrol engined cars still sell 100 times more
@@broshido2745 - Today maybe, but not for much longer. The slide valve is the achilles heel in my opinion.
@@rogerfroud300 no they're stick around for atleast another 2 decades if not more, combustion engines still serve more broad practicality especially when it comes to weight to range ratio.
@@broshido2745 Hybrid maybe and even then I doubt it because Toyota has already pretty much perfected it, but some like Daimler(Mercedes) have already announced they won't spend a single € to develop a newer gen of ice engines. The writing is on the wall for those who want to see it.
There is also a pre-chamber ignition method. Used in F1 and LMP cars and finally coming out for a road car with Maserati MC20. It practically eliminates two stage combustion and knock while being a well known and ironed-out technology.
Its a great idea, I can definitely see that sliding valve working flawlessly for at least 15k miles !
*looks at the amount of moving parts, looks at the concept, looks at the theory* so... a split cycle engine with even more moving parts and even more complex?
Two-stroke engines are by far the simplest and have been displaced from cars many decades ago.
Despite their simplicity, cheaper maintenance and never needing an oil change, their inferior efficiency and worse emissions have made them obsolete.
Same will happen to other engines that will successively be replaced by electric motors over the next decades.
When exactly? Even the experts don't agree, so we'll just have to wait and see.
Built an air compressor out of 2 cylinders on a VW air cooled 4 cylinder engine once..same principle.
daszieher I mean electric vehicles make up less than 2% of the vehicles on the road I don’t see them hitting 10% even within 50 years
daszieher until you can buy an electric car for $1,000 like a cheap civic that’ll run another hundred thousand cheaply electric won’t make sense
@@mercury0214 Exactly. The government will have to force combustion engines off the road. Like they are doing in the UK, Europe by driving up the road tax's for diesel and petrol engines. Plus making exhaust emission laws that are almost impossible to meet and maintain.
I was interested until it got to the slider valve.
Yeah, I got a bit hung up with that also but apparently, most of the pressure is used up during the power stroke and the exhaust valve is timed to limit the pressure to not overcome the slider valve. I'm with you, poppet valves have reigned for a long time and the fingers of a slider valve is a very troublesome arrangement with the pressure considered. I recall many decades back experiments being done with 'swing valves' which were mounted more or less like rocker arms with a valve head on the end - it went nowhere apparently, never saw any further examples published.
@@tripplefives1402 Yes, and they didn't work well at all
You can look at WWI plane rotary piston engines such as the French Gnome/Le Rhone to see why mixing/breathing chambers are an incredibly terrible idea as well
@shane
Oh, now we're talking...
@shane turbo-compounding is a great way to decrease mechanical reliability.
The ginormous R 4360 engines used on the dc6 and -7 piston airliners had a trio of "power recovery turbines" that the exhaust gasses blew through to power the crankshaft through a clutch. Any mechanic that worked on the engines called the PRTs "parts recovery turbines", they did a huge number on engine reliability. Like needing rebuilds four times as often! 500 hours time between overhauls, when a non turbo compound engine would last 2000hours!
This topic is super complex and the paper explaining it is like 625728378289 pages long yet this dude explains it all in 13 minutes. Legend.
I remember seeing something like this several years ago. They called it "the 5 stroke engine." It was under development around the same time that Duke engine was being developed, and a few other thinking outside the box internal combustion engines.
Just like my bbq burner slidervalve? First thing to get stuck and break. Good luck with this one.
Not just like. I'm pretty sure the engine's slider will be made with more than $0.04 worth of material and would also have a bearing surface and lubrication.
Amazing to see how researchers are improving engine technology beyond any of my wildest imagination.
eventually even the smart people brains will hit the cap and AI will take over inovation, churning new ideas, concepts, engines, optimizations, faster then anyone could. Even allot of theses inovations we see today already are only possible because of new powerfull computers who simulate many projects that would too much work for humans alone to do on a simple pen and paper way.
Internal combustion engines have so much potential! Imagine an engine with HCCI or EI with the electro-pneumatic valve actuation found in the Koenigsegg Gemera.
Thysen-Krupp presta delta valve control
Yes and it breaks down every time you attempt to start it
Really well explained for non engineering types like me. Good video
Looks like a whole lot of engine for not a lot of power
yeah, only one cylinder is making power and that one cylinder is moving the rest so the amount of power loss is ludicrous
@@neevdash450 That 2nd expansion cyl is making power too. It's like a 2+ expansion chamber steam engine. Also, it ain't an engine for hot rods.
@@CompTechs It seems like the BSFC of the engine doesn't warrant the cost or repair bills that could possibly exist. In steady state power productions there are much less complex and reliable means of power. In heavy industry there are far superior means of power production. In racing or even mild automotive applications this is so far down on the possible uses that flatheads would be brought back before this was thought about.
this divulged into utter bs, engine development is long complete, but what would yt channels do if it wasn't for mazda and others' silly dreams. that slide valve, how long untill it breaks there? come on....
Probably best used for powering generator for electric drive vehicle
No idea how to start this engine when its -15°C outside
Yeah some places get down to -40 ° and my diesel refuses to start. Same problem
Ether!
And glow plugs
And glow plugs!
And glow plugs!
This reminds me of the creation of the triple expansion tech of steam engines. My (ignorant) immediate reaction is, you appear to have one "firing" cylinder moving four cylinders. To potentially have enough energy (4 cylinder size) to move a car, you would need the engine to have 4X4 = 16 cylinders. Neat video / potential tech, Thanks.
Opposed piston 2 stroke still a whole lot more viable option for future
Mamadh Haryadi yes, as made and used by Commer lorries back in the 1950's. Sounded gorgeous. !
It made bang into tremendous power and noise !!!
It’s definitely an interesting concept.
My main issue (which you actually brought up) is the reliability.
Generally more complexity results in a decrease in reliability.
I’d rather have a less efficient engine that’ll last forever. In a normal road car at least.
Track is a separate conversation.
can't be less reliable than a range rover
My problem would be power/weight. As i said above, with this you essentially have a once cylinder engine that's the size of a 4 cylinder, with loads of parasitic loss.
2:55 You have rich pockets, you have lean pockets. Jim Gaffigan wants to know; "Where are the Hot Pockets?"
Me : this is just a 2 stroke with fuel injection
Him: it’s basically a 2 stroke
Me: ok cool I get it
Premixed fuel injection yes.
Open-valve, pre-mixed fuel injection at high pressure. Closer to a turbojet than a 2-stroke really.
@@Wingnut353 I mean sure
I want to say that I really appreciate your videos. Your content makes up for the other stuff on RUclips. Like the garbage I see children watch on the internet.
Please continue to explain things in simply understood ways. You and Practical Engineering are the modern equivalent to the ancient training videos. Basic concepts, straightforward explanations, better educated viewers. We might now be living in 1984 (and have done it to ourselves), but the electric screen has also finally reached its potential as an educator.
I salute you for being a part of the solution.
7:57 You said, that the combustion is going to have less pressure, than the initial air-fuel mixture. The initial air-fuel mixture however has less pressure, than it takes the gasoline to ignite. Therfore, the final combustion must have less pressure than just regular gasoline explosions in a usual cilynder. (if a
Traditional engines have high pressure for a short period. This has a lower pressure for a longer period (near constant pressure burn, slow). This increases the area of the pressure-volume diagram, increasing work done.
The compression ratio refers to the difference in volume, not pressure! The effiency is therefore less dependant on a pressure differential, but more so on the difference in volume.
@@EngineeringExplained I thought you wanted to burn all of your fuel as soon and quickly as possible. So you can get as much work out of the expanding gas. Burning fuel when the engine is a few degrees away from bottom gets you much less work than burning the same amount of fuel at the top of your stroke
@@EngineeringExplained yeah, but "work done" isn't the metric. Efficiency is impossible unless nearly all of the fuel's energy is converted to heat/pressure during dwell. After dwell the only issue should be "clean up", which MUST be largely done relatively early in expansion because otherwise the "clean up energy" is wasted. It's not like any system harvesting energy from a catalytic converter will be more than a few percent efficient.
Always an amazing engine class 🙏🏻
Really appreciate your efforts producing videos about automotive technologies.
If it is reliant on chamber temperature to auto ignite, I would think cold starting would be an issue. Prob need intake heater or glow plug
Seems like a recipe for soot buildup in that pre-entry reservoir.
There's only compressed air mixed with fuel there. How would that build up soot? The fuel burns as it enters the "power" cylinder. Nothing burns in the reservoir, nor do any exhaust gases go there. Fuel is also good at cleaning stuff, such as valves in engines that have fuel injectors in the throttle body. So it's the opposite of soot build-up. Probably the cleanest part of the engine.
@@Kepe I understand that part of the design. However, you'd notice that fuel burn occurs during the opening of the valves and it will inevitably cause some burnt gasses to seep through the "high pressure" reservoir. Though the point you made with fuel being a cleaner does make sense, we've still seen examples of injectors clog up despite them supposedly having high pressure fuel sprayed out of them. Of course, the difference is that injectors are inside the combustion chamber as opposed to this design. The only point I'm trying to make is that those valves seem like the weak link in this design, really. Especially due to its "sliding" design as opposed to a cork-like seal found in traditional ICE. I guess only time will tell how well this engine fares.
@@Kepe soot came from chemicals used in Petrol additives and also in storage tanks, that's why 4stroke engine is made to eradicate all of that issue, if own a two stroke engine you know how this engine will fail eventually
@@Kepe soot came from chemicals used in Petrol additives and also in storage tanks, that's why 4stroke engine is made to eradicate all of that issue, if own a two stroke engine you know how this engine will fail eventually
Since the reservoir is higher pressure than the combustion chamber, soot would not be able to back flow in there. They use the same concept for operating theaters. The operating room is kept at a higher pressure than the outside rooms so airborn dust cant float in.
If anything, you would have to worry about leakage from reservoir to combustion mid cycle. Then again the combustion chamber MUST be at a higher pressure than the reservoir during combustion. Otherwise you wouldn't need combustion and could just run off the reservoir pressures. If the seals leak you could get some back flow there.
Sounds like that engine would be well suited for a generator.
I've been watching you for a couple years now. No I have not accidentally started my own online work training's with "Hello, and welcome." and concluding with "If you have any questions or comments, please feel free to leave them below." Great stuff as always good sir!
You are brilliant, love the videos please keep doing what you do
I always thought lean pockets were an abomination.
So hot pockets are good enough for you?
LadyAnuB See Jim Gaffigan about this.
@@LadyAnuB Lean pockets are just like hot pockets, just less fat and calories!
Interesting how things come around and go around. I'm glad to see someone trying to use the principals of the 1906 Compound and the Honda CVCC . Probably never find high hp, but there should be efficiency in there somewhere.
Sometimes where theory meets practice, the water muddies.
Those old Honda CVCC engines would carbon up the tiny intake port for the prechamber, and the things would run terrible until you pulled the choke out (thankfully they had manual chokes!) and richened the mixture into the main cylinder.
Of course, that killed fuel mileage and the HC emissions went off the scale, but at least it would get you where you’re going ...
If you draw a jet engine next to the entry ignition engine, they look pretty much same. The first piston is like the low pressure compressor stages on a jet engine, the second piston is just like high pressure compressor stages, the mixing chamber is sort of but not really like the combustion chamber on a jet engine, the third piston is like the high pressure turbine stages, and the fourth piston is like the low pressure turbine stages. The only difference is that pistons are in the place of compressor and turbine blades and unlike a jet engine, entry ignition doesn't undergo continuous combustion.
Entry ignition - What a great Idea I am and one day I might actually work! Spark Plug - Hold my beer, been doing this since 1807!
This does seem like a lot of moving parts, and since rotary valves make a lot more sense but have never caught on, I'm not too encouraged about the slider valve.
Side question: has anyone tried just using the exhaust rotor of a turbo to generate electricity in a hybrid? Seems like a simpler way to leverage exhaust pressure/heat, and who cares about lag time?
What about packaging? You’re taking up the space of a 4 cylinder with only one of the pistons doing the work (granted 2 stroke vs 4 stroke), but still...
That was basically my thought.
An equivalent to a V8 would have more cylinders than a Bugatti lol
What I was thinking
I imagine this engine is focused on efficiency, with power a far second, or third. Most people are perfectly fine with 200hp, which this should reach, as it's forced induction
And any application that packaging isn't a top priority it would be fine, like generators
@@gutserker yes, generators and some marine engines I guess would be ok with it
For high efficiency I could see a two strock diesel, multi-stage turbos and direct injection allowing a 30 to 50 compression ratio. The turbo would be coupled with the crankshaft by a planetary gear box acting as a supercharger/turboprop. So the pistons would take care of the high pressure and no lag tork response and the inlet turbos would take care of the low pressure compression (1 to 10 atm.) and cool it with an intercooler before sending it to the cylinder head. The exhaust turbo would contribute to the engine tork (like a turboprop engine) and keep the combustion gas at higher pressure for a longer time allowing a more efficient burn and therefore creating cleaner imitions. This way you also remove the exaust cam friction and double the amount of cylinder heads combustion for the same amount of internal friction.
There was a British engine in the 1980s that never went beyond prototype. It had a small primary air cylinder where rich mixture was mixed and ignited. The part-burnt gas exhausted into the main cylinder containing hot compressed air where the burn completed. It was clean and efficient.
I remember seeing a local interview with the guy that patanted this. He was going to license the technology to Toyota but then never heard anything since then.
DieselPunk Cummins ahh, did big oil knock him off? Shades of Ralph Sarich’s 1972 Orbital engine...😜
Wow. This makes a hell of a lot of sense. I was wondering how F1 would go to a 2 Stroke engine in the future after these V6 Turbo Hybrids. This explains it I guess. 👌
Avais Hussain ah, but F1s then need a sound system to enhance engine noises to keep fans happy? 😆
@@kdkd693 nah two strokes sound amazing already! and It gonna have screaming high rev's!
@@inrg3688 right, if they apply their technologies to it they might make them sing like some rotaries
I can only imagine how much space this would take to operate, regardlessof how many "cylinders" it possesses, since fewer cylinders means more attachments to precompress the air.
Thinking of that slider valve, I imagine you could determine how wide it opens to act as a throttle control, but really electronically controlling the amount of fuel injected would help with that.
Now how thick would those slider valve plates have to be to resist the heat and pressure of that combustion chamber? And how would it be lubricated to prevent siezing as the metal expands when heated? And carbon buildup could very well prevent it from working.
Might be good for an alternative low carbon fuel though!
Pretty cool idea though!
In the 1970s Honda had their carbureted CVCC Engine in the civic. It had a divided combustion process where the main part of the cylinder was lean and a much smaller thimble shaped pocket in the head with a rich charge that was spark ignited and blew into the main cylinder like a torch increasing efficiency and lowering emissions to the point that it didn't need a catalytic converter.
7:46 I could literally hear my brain stalling out
9:00 I thought that supposed to be motorcycle tire with chain
@Engineering Explained
3:40 we can control the ignition timing by changing the compression level . i mean there can be something like extra isolated valves (air in the combustion chamber cant move behind that valve) on the cylinder head to move up and down by just some millimeters to adjust the compression level in the combustion chamber . so by increasing the compression level earlier it can ignite earlier than normal.
After being completely amazed, the first thought I had was "but how does it start?" almost two years later I'm still left wondering... "How does it start?" But it's still super cool...
one quick question: how do u make the first combustion when starting the car? from my understanding u need combustion to generate heat then heat leads to another combustion, but before starting there is no heat.
You'd need glow plugs like in a diesel for the same purpose.
It would probably need to spin over more then once before start up, Raising temps. Like a diesel that doesn't have glow plugs
@@hopsgarage5513 If compression is high enough you don't need to... at 20:1 compression you almost don't need glow plugs and Detroit 2 strokes don't' have them (they get an air charge from a blower + compress that then boom all without plugs and as long as the engine isn't worn out they start up in a jiffy at above freezing temps and you can start them below freezing with some extra turning over as you mentioned). My 3-53 detroit will pretty much fire up on the first revolution.
@@Wingnut353 having high compression doesn't mean quick starting, Nor does it mean no glow plugs. The blower on a 53,71 or 92 series is to clear the cylinders of exhaust and provides little performance gains hence the turbo addition later. Sure there are some quick starting diesel but I've never seen any start in one revolution.
Compressing air makes heat. The higher the compression ratio the higher the heat is.
How would one start the engine if the combustion chamber is cold?
Glow plugs?
only one cylinder will fire not the 3,
Thank you! I was thinking this too.
@@hallkbrdz what about having a block heater option with the glow plugs?
Notionally very interesting, but it reminds me of many attempts to optimize various machines that become so complex that either mechanical reliability or manufacturing cost or maintenance, etc. overwhelms any efficiencies gained. In grad school, I went out to sea with a student who had built a high-resolution sonar array similar to a phased-array radar. Great idea, great resolution - on land, or in a tank. At sea, with rolling ship, waves crashing about, the entire spider web was impossible to deploy and maintain as a planar transducer array. The practical overwhelmed the theoretical advantages. I would love to see an experimental test bed of this form of IC engine that was tunable and measurable, from which to derive some costs and complexity data. It might well lead to a simplification path that would be even more effective. Interesting tutorial, as always.
I've been mulling over, for some time, the idea of one cylinder pressurising a working cylinder. Somehow I never managed to think it all through so it was a revelation to watch this video. Incidentally it seems to me that, in a standard otto cycle engine, using an exhaust driven turbo-charger is a good idea because it uses the not inconsiderable energy still present in the expanding gas when the exhaust valve opens. I also think that the turbo should be kept spinning at some minimum speed by an electric motor-generator as in an F1 ERS system. In a road car, at higher revs when the turbo is being spun at sufficient speed by the exhaust gas, the motor-generator could be switch to generation thus making a separate alternator un-necessary.
Lubricating that slider would prove to be a nightmare. The only way this could be done would be to use castor oil, which poses another set of problems. Also, the efficiency of this scheme would seem to be less due to greater internal friction. And this would be a very expensive engine to build; With electric cars on the horizon, I doubt any auto company would want to spend the money to go down this route. Great video!
Intake/exhaust poppet valves are not lubricated in the combustion chamber. Mostly up/down motion, but they also can rotate. Fair point though, as described the slider mechanism would be challenging to lubricate.
@@EngineeringExplained My original design used an I/O valve that combined a poppet (to handle pressure) and a way low pressure rotating gate. The engineer I talked to from Volvo's SuperTruck engine development team said that going with such a system would take a decade and a huge amount of money to bring to market, and there'd be no guarantees. It's not like a company is going to put untested stuff into a product that, if it proves to not be durable, would sink the company. So those guys will have to do all the development on their own time and dime. This alone just about guarantees that the engine you described will not come to market (unless your name is Bezos). So, by the time a single engine was sold the patent would be close to expiring. Not a good bet.
And, not contradicting you, just adding my two cents, poppet valves are adequately lubricated for rotational movement because the stem is lubricated, there's no rotation when they're closed, and when they're open the valve and its seat don't touch.
Improving international combustion engines is important. But they did improve some emissions like diesel with diesel exhaust fluid. Could you do a video of how diesel exhaust fluid works?
When the fuel is sprayed into the mixing chamber, it will ignite and expand into the pressure reservoir and mixing chamber first. When the slider valve opens up, then the expanding pressure from the burning air/fuel will start pushing down on the third cylinder. So, the volume of the pressure reservoir and mixing chamber become part of the third cylinder's volume.
I always enjoy your videos with their down to earth explanations. Thank you.
6:35 Process seems kind of like a mechanized backdraft
ornately over-complicated. An opposed piston system with the intake valves in the pistons using a roots to pressurize the crankcase would beat it any day of the week.
@@prjndigo Then how come every car in the world isn't using this sort of setup and getting extreme effeciencies?
Seems like putting more technology into transmissions and gear ratios are a simpler way of making a car more efficient.
@@lysolmax they are quite hard to maintain and are expensive to produce, ships had them in 70ies
@@lysolmax cheap-ass companies and patents
I see the potential for the first cylinder to have a larger bore and the second cylinder to have a longer stroke.
Would make for a pretty gnarly looking crankshaft. I think if this were to be used they would probably use a supercharger instead of 2 extra cylinders
@@NodmadTroy maybe it could work with opposing pistons layout like boxer. Not sure about this tho i am not an engineer xb
Besides improving the combustion engine, what if we use all possible energy like also recovering the heat generated by the engine (and usually vented by the radiator) for an external combustion engine like a Stirling engine, build that setup with hybrid battery pack and profit? Combustion engine linked to wheels via clutch + cvt, stirling engine only generating current, electrical engines on the wheels and the chance to disengage the combustion engine via the clutch to run on full electricity if we have enough charge in the batteries. OFC I said Stirling engine because it is the first that comes into my mind, but in its place you can put the most efficient external combustion engine you can think about, with size considerations regarding how much heat it can utilize.
Starting on a cold day looks like a barrel of fun.
Sounds like it might be similar to a design by Smoky Yunick from last century. I think he called it "vapor cycle."
His "Hot Air Engine" in a Pontiac Fiero. It used turbo exhaust gas to super heat the fuel.
Hold on, a detailed explanation on a whiteboard with diagrams!! Yes, I want that please.
It feels like a class, and it's impressive; I like it.
Great stuff thanks. Like the animated explanations most.. little clips makes it clear less talking necessary
Another noteworthy benefit is a convenient capture point for high pressure bleed air. There are a lot of possibilities such as: pneumatic start (via the same port as the capture point), bleed air operated HVAC blower, air suspension, seat cooling, electronics cooling, external compressed air utility hookup.
Rich pockets, lean pockets. HOT POCKETS!
I seen the Hot Pockets girl in the news recently
*Very Interesting , Would be cool to see one running!*
I can also give another drawbacks, which is the main challenge of displacing an engine properly. It is quite difficult to arrange between engine configs, such as Inline-4 (shown), Inline-6, V6, V8, etc.
Tony, I am limited with the technology of my time, but the time will come and you will complete this project.
I am all in for efficiency! Awesome ideas there.
How would you do a cold start if ur relying on heat to ignite the fuel?
ff, nice question
Maybe have a spark plug for cold starts -- could be doubled as a way of timing ignition in a limp situation or warming cats
I can skip most of your sliding etc by adding a turbo down stream from the carburetor/injector as a heater/mixer to raise the pressure and the temp or the incoming charge. The air fuel mixing is done in the intake tract. You can dump the extra cylinder and accomplish the same thing.
The slider valve is going to be one HELL of a challenge to make really reliable parts.
very cool, it reminds me of triple-expansion steam engines.
Exactly my thoughts when it is explained. It is similar to it. But using gasoline instead of steam.
While NOT for road applications, a triple expansion steam engine with Corliss valve gear is QUITE efficient. The overall efficiency "gotcha" that's never discussed with internal combustion engines of any sort is the amount of energy consumed in preparing the fuel for use. "The perversity of the Universe tends towards a maximum." The molecular structure of distilled crude oil has abominably bad anti-knock properties, for both the gasoline (octane #) and diesel (cetane #) fractions. Energy is expended to alter that undesirable structure into something whose anti-knock properties is OK. ANYTHING that burns, regardless of molecular structure, can be used to generate and superheat steam. Of course, the combustion process must not be a significant polluter. Lunch is NEVER truly free.
Hi plz can you explain why diesel do Runaways. And what to do if it happen. Thanks ❤️
Yes👍
✊yes
🤘☝️
A diesel often burns oil when it goes runaway. The other cause would be a fuel leak inside the cylinder.
It is very difficult to stop in an automatic transmission. But in a manual it's just as easy as stalling the engine.
it happens when an engine oil (too much of it) finds it's way into the combustion chamber. Either sucked in with the air through a leaky turbo or simply through a crack in the block or head (I think). Since a diesel engine can run on oil, cutting of the fuel pump or a battery won't do you any good, because it sustains itself by pulling more oil in and doesn't require a spark to run.
If that happens, your best bet is to stop the car, stay on the brake, put in the highest gear and quickly release the clutch, which should stall it out. If you have an automatic, you could try to plug the air intake with whatever you can find. However, modern diesels have a throttle body that should close when you turn of the ignition, starving it of oxygen :-)
My wifes 2017 Hyundai has the 2.0 Atkinson engine. It does well for efficiency if you drive it with that in mind. 37 to 40 Hwy MPG the 6 speed gives it plenty of pep down low. Very happy with it vs the direct injected alternatives
This must be incredibly new because through a google search nearly all articles explaining entry ignition include your video.
The second stages reminds me of the Scuderi Split Cycle Engine
This video makes me feel like I need a nap.
Reminds me of the "twingle" two stroke engine on a Puch motorcycle. The rear cylinder contained the crankcase transfer ports, and the front cylinder had the exhaust ports. The head covered both cylinders with a common combustion chamber.
Excellent presentation, congratulations from a mechanical engineer who is a also a teacher!
Seems to work like a tripple expansion steam engine from 100 yeara ago. Carbon build up will be fun on the slider valves. Would like to see a running version.
My wife asks me what I’m watching and I replied “I’m watching a very smart man explain engine technology and many other interesting concepts.
she thinks that you're watching porn and that this is your cover up lie
@@HkanAktas I think your right 😂
Grate ! :)))))
Daniel Bryant
Reminded me of the movie "To Kill A Mockingbird" as Acticus is leaving the courtroom.
They stand and the man tells the boy to stand, "A great man is passing..."
It's somewhat a mix of many ancient tech.
The hot air reservoir is basically how hot bulb engine works, and two expansion pistons is the regular compound steam engine principle. Sliding valves are also not new at all. Again, steam engine uses large sliding valves, and rotating sleeve valves were a (oil-greedy) thing of early performance automobiles.
It helps to know that piston engines are essentially air compressors with a kick.
stil i love my 1.9 TDI PD !!!!
Every time he says "aaaaannndd Welcome" I feel like something dies.
Yeah, my feeling of being unwelcome.
You should seek help for that reaction. It's not normal.
Your next
Very cool and innovative, I hope we get at least 1 production engine with this technology so it can be evaluated thoroughly.
Jason, would it make sense to change two things?
1.) Use an electric supercharger instead of pistons. Have the supercharger's battery be charged by the work done by the engine, which should be greater than the force to bring in air at a given pressure.
2.) Use a pressure valve, instead of a slider valve. Given a high enough pressure, the force of air in the upper chamber should overcome the force of the spring keeping a valve closed, pushing open a valve.