Most Advanced Internal Combustion Engines

AI Thread Summary
The discussion centers around the advancements in internal combustion (IC) engines, highlighting various technologies such as BMW's Valvetronic and direct injection systems. Participants debate the classification of SCRAMjets and the efficiency of diesel engines, noting that large ship-based diesels can exceed 50% thermodynamic efficiency. The conversation also touches on the potential for diesel hybrid systems and technologies that disable cylinders at idle to improve fuel efficiency. Additionally, there is mention of the challenges and innovations in starting diesel engines, including the use of compressed air and preheating methods. Overall, the thread explores the complexities and advancements in IC engine technology.
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Hey guys ,can u just let me know about the most advanced or developed
IC engine.Plz help.
 
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Does a hypersonic SCRAMjet qualify as internal combustion, or does the combustion chamber have to be closed at the point of ignition to qualify?
 
How about the BMW VANOS engines, pretty advanced. Also, direct injection gasoline engines are now availale to the public. Electronic control systems have progressed an incredible amount in the last few years too.

What is the purpose of the question?
 
bags, it would be helpful if you were more specific in your questions. If you give some context to why you're curious about this, or what it is you want to know about it, or do you just want opinions on what people think IS the most advanced engine, etc.
 
How about Caterpillar's ACERT Diesel engines? o:)
 
There are many ways to measure "advanced": lightest, lowest emissions, best power-to-weight, best power-to-volume, greatest total power, highest efficiency, etc.

However one of the most important is peak thermodynamic efficiency. In that respect diesels are the most advanced. Large ship-based diesels can exceed 50% thermodynamic efficiency, which is incredible.

Smaller automotive diesels if using the HCCI design could theoretically achieve 40% peak thermodynamic efficiency:

http://www.llnl.gov/str/April04/Aceves.html

One of the most advanced mass production gasoline engines is BMW's valvetronic design, which is much more sophisticated than double VANOS:

http://www.bmwworld.com/technology/valvetronic.htm
 
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i would have to say that the most advanced IC engine would have to be one that has been converted to run on bio diesel or on keroscene.

just out of curiosity, has anyone seen or heard of a desile engin that incorpeates the technology that disables 1 or 2 pistions so that they are not firing when at idle? or howabout a diesel hybrid (instead of using a gasoliene engine to power the generator. i haven't heard of either of these, but they both seem like they would be a good way to up the MPG's. :cool:
 
Gigabyte111 said:
i would have to say that the most advanced IC engine would have to be one that has been converted to run on bio diesel or on keroscene.

A normal Diesel engine will run on biodiesel without any conversion.

just out of curiosity, has anyone seen or heard of a desile engin that incorpeates the technology that disables 1 or 2 pistions so that they are not firing when at idle? or howabout a diesel hybrid (instead of using a gasoliene engine to power the generator. i haven't heard of either of these, but they both seem like they would be a good way to up the MPG's. :cool:

Do you mean a Diesel hybrid car? Don't see any problem with this idea, except for the commercial reasons which are currently restricting the sale of petrol hybrids.
 
Gigabyte111 said:
just out of curiosity, has anyone seen or heard of a desile engin that incorpeates the technology that disables 1 or 2 pistions so that they are not firing when at idle?

They have been doing this for years. I worked at Honda at the time when they were coming out with their design for it. I believe they first put it on the Odyssey. Anyways, they shut down an entire bank of cylinders when under low load. Basically, it used VTEC-like technology to hold the valves open (so there's no loss of power compressing air), then since everything else is computer controlled, it just cuts spark and fuel.
 
  • #10
brewnog said:
Do you mean a Diesel hybrid car? Don't see any problem with this idea
I can think of one, but I might be mistaken. Hybrids apparently start and stop the gas motor when the computer determines that extra power or electrical augmentation is needed. With a Diesel, the warm-up time for the glow plugs would cause a serious lag in starting (wouldn't it?)
 
  • #11
minger said:
They have been doing this for years. I worked at Honda at the time when they were coming out with their design for it. I believe they first put it on the Odyssey. Anyways, they shut down an entire bank of cylinders when under low load. Basically, it used VTEC-like technology to hold the valves open (so there's no loss of power compressing air), then since everything else is computer controlled, it just cuts spark and fuel.

Nope, this is on a spark ignition engine, it's pretty common practice now. I don't know of any CI engines which do it though, anyone?



Danger said:
I can think of one, but I might be mistaken. Hybrids apparently start and stop the gas motor when the computer determines that extra power or electrical augmentation is needed. With a Diesel, the warm-up time for the glow plugs would cause a serious lag in starting (wouldn't it?)

Good thinking. My Diesel engines are all large enough not to need glow plugs (big cylinders = not much quenching of temperature through cylinder walls, and direct injection so no prechambers with large surface areas). Modern direct injection Diesels' glow plugs only come on for a few seconds, even in cold conditions, but I'm sure that with some moderately sophisticated stratification (and perhaps boost limited fuelling, I'm assuming you'd want a small, turbocharged engine for this) you'd be able to get cold start load acceptance good enough to be pretty on-demand. You could use a block heater to keep the engine at a nominal warm temperature whilst not needed, it's a bit of a trick you can use to air cold starts.

Can anyone be bothered to look up what current glow plugs draw, or think of any other methods of quickly starting a cold Diesel, short of immersion heaters or ether? I suppose it wouldn't be too radical to use the engine when starting the vehicle, and then to start it up periodically during motoring, even if not needed, just to keep some heat in it?
 
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  • #12
brewnog said:
Can anyone be bothered to look up what current glow plugs draw, or think of any other methods of quickly starting a cold Diesel, short of immersion heaters or ether? I suppose it wouldn't be too radical to use the engine when starting the vehicle, and then to start it up periodically during motoring, even if not needed, just to keep some heat in it?


here's an idea, devise a system to capture the heat generated by the electric drive moter and then channel that heat (with a liquid that holds heat well) to the diesel engine to keep it warm.

Just a thought
 
  • #14
brewnog said:
Nope, this is on a spark ignition engine, it's pretty common practice now. I don't know of any CI engines which do it though, anyone?

whoops, didn't read closely enough, and didn't realize we were talking CI
 
  • #15
Not necessarily what you think of under hybrid, but there are definitely industrial vehicles (like locomotives) that run using a diesel generator and electric motors. I think this is primarily because the torque characteristics of electric motors are preferrable.
Googling diesel-electric yields, among other things:
http://www.military.com/soldiertech/0,14632,Soldiertech_Shadow,,00.html

Compressed air is a popular method for starting marine diesels.
 
  • #16
NateTG said:
Not necessarily what you think of under hybrid, but there are definitely industrial vehicles (like locomotives) that run using a diesel generator and electric motors. I think this is primarily because the torque characteristics of electric motors are preferrable.
Googling diesel-electric yields, among other things:
http://www.military.com/soldiertech/0,14632,Soldiertech_Shadow,,00.html

Yep yep, but automotive applications are more demanding, because when the driver puts his foot down, he needs powere right then, and as Danger pointed out, Diesels have more trouble than petrol engines from cold under these circumstances. Large equipment and locomotives generally use a Diesel engine as their prime source of power (actually generating all the time), rather than switching on and off to supplement batteries as and when required as with a hybrid vehicle.


Compressed air is a popular method for starting marine diesels.


Indeed, but only as an alternative to an electric starter motor. It's not pumped directy into the cylinders, and does not any more heat into the engine than an electric starter.

I've heard about preheating the fuel, and even the inlet manifolds, but would doubt if this is more efficient or effective than block heaters.
 
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  • #17
NateTG said:
Compressed air is a popular method for starting marine diesels.

I, in my 12 years of owning many large diesel powered boats/ yachts, I have never in my life encountered a marine diesel started by compressed air, from 15' boats all the way up to a 52' twin turbo diesel powered yacht, have ever heard of a boat started by compressed air, or even have a air compresser on board. i know that for a fact you are required by law (or regulation, not quite sure which) to have atleast two 12v batteries for each engine. it is possible that the lagrer (container ships) ships do this but never in the boats i have had.

zac:devil:
 
  • #18
Gigabyte111 said:
I, in my 12 years of owning many large diesel powered boats/ yachts, I have never in my life encountered a marine diesel started by compressed air, from 15' boats all the way up to a 52' twin turbo diesel powered yacht, have ever heard of a boat started by compressed air, or even have a air compresser on board. i know that for a fact you are required by law (or regulation, not quite sure which) to have atleast two 12v batteries for each engine. it is possible that the lagrer (container ships) ships do this but never in the boats i have had.

zac:devil:


I have. They're the noiseist things in the world. Don't be near one without really good earmuffs if one ever starts within 50 yards of you!
 
  • #19
Is that a compressed air starter in the one scene in the movie "Maximum Overdrive"? As I recall its the newlywed couple being chased at a gas station.

Diesel hybrids are going to happen, but stateside the now highest sulfur diesel is soon to be some of the lowest sulfur diesel and has things all mixed up for the manufacturers. Its not like they don't produce millions of diesel cars for Europe, and there the gas is like $6-$8 a gallon so the idea of a hybrid makes that much more sense.

GM is making diesel hybrid city buses, and some of the heavy-duty truck manufacturers are suppossed to have some hybrid garbage trucks in the works. With both vehicles making frequent stops, its a great optimization for gains in efficiency. I can imagine that once the ROI is attractive on the additional cost carriers like UPS/FedEx/USPS and other fleets will incorporate hybrid into their frequently stopping vehicles.
 
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