5 stroke engines

[ronan]

Never heard of this before, i thought it was a wee-take, but all it seems to be is an extra cylinder that burns the mixture a second time.

 

[octo0072000]

interesting but when will it get into production is the problem maybe 10 years ??

 

[ronan]

interesting but when will it get into production is the problem maybe 10 years ??

If VW get into panic mode maybe six months . But there is nothing too radical in its design, i don't see why it can't be a goer now.

 

[rtbcomp]

So what's the downside?

 

[slim_boy_fat]

Well, Ilmor have been around long enough to know what they're doing.

 

[colnerov]

Hmm, it works on the compound principle as used on steam engines. No mention of any improvements on emissions, although if it using less fuel then there will be less emissions. It says lower exhaust temperatures so the catalytic converter won't be as efficient. If they go to direct injection then NOx emissions will increase. I'm not convinced, time will tell.

Colin

 

[ronan]

Yes it struck me as being like the triple compound steam engines of old. The mixture being burnt twice, that should reduce emissions somewhat.

 

[the snooper]

I watched the video and I think they have totally got the name wrong it's not a 5 stroke at all the strokes of an engine refer to how many times a piston travels up and down a cylinder to create the power ie induction compression ignition and exhaust which is what that engine still does and Colin stated it's exactly the same principle as a 2 stage steam engine so if anything it should be 4 stroke 2 stage engine

 

[julianthegypsy]

It's not really burning twice, it's a double expansion engine. I would have thought that would cause excessive back pressure in the primary chamber looking at the video, but it would open up the exciting possibility of throwing clean fuel and air at the secondary chamber for a burst of power when needed, much like the double expansion steam engines where you could throw a lever and dump high pressure steam into the larger secondary expansion chamber effectively doubling power. They don't seem to have thought about that possibility though...yet.

 

[Spark plug]

Interesting concept, until one of the big oil company's buy the patent and put it in a vault some ware.

 

[colnerov]

It's not really burning twice, it's a double expansion engine. I would have thought that would cause excessive back pressure in the primary chamber looking at the video, but it would open up the exciting possibility of throwing clean fuel and air at the secondary chamber for a burst of power when needed, much like the double expansion steam engines where you could throw a lever and dump high pressure steam into the larger secondary expansion chamber effectively doubling power. They don't seem to have thought about that possibility though...yet.

Hi, I'm not sure about introducing fresh air and fuel into the secondary chamber for more power. It works on a steam engine because the extra charge of steam is at a higher pressure than is present in there already so it gives the extra boost. On this new concept it would be introducing it into a suppressive atmosphere i.e. high in CO2. When does it get compressed and when do you ignite it? If it's ignited when the secondary piston is at the top of its stroke, which would be best so it helps push it down, the primary piston is on its way up pushing its exhaust gases into the secondary cylinder, so it would meet resistance and sap power.

Because the engine is working the air and fuel twice it would need a much larger turbo to be effective. For me this raises more questions than answers.

Colin

 

[colnerov]

Interesting concept, until one of the big oil company's buy the patent and put it in a vault some ware.

Hi, I'm not sure they would do that because it's not replacing hydrocarbon demand. like electric or natural gas or wind or anything else other than oil.

Colin

 

[sardine]

Its crazy, these new internal combustion engines won't take off, you mark my words.

 

[colnerov]

Its crazy, these new internal combustion engines won't take off, you mark my words.

Oh yes, I agree.

 

[AndyStobbs]

All these wacky designs are rubbish. Idiots modelling stuff on computers and claiming benifits, 90% never even exist for real. The ones that do are hopeless under powered, or don't last or simply don't work right.

 

[upinsmoke]

hi not such a bad idea. remember the two stroke stepped piston, with modern control systems and maybe another piston, could be more efficient .

 

[dannyp]

its a nice idea, but more bits maybe means less reliablity, also if your pulling all the energy out the exhaust how is teh turbo going to behave

 

[julianthegypsy]

Hi, I'm not sure about introducing fresh air and fuel into the secondary chamber for more power. It works on a steam engine because the extra charge of steam is at a higher pressure than is present in there already so it gives the extra boost. On this new concept it would be introducing it into a suppressive atmosphere i.e. high in CO2. When does it get compressed and when do you ignite it? If it's ignited when the secondary piston is at the top of its stroke, which would be best so it helps push it down, the primary piston is on its way up pushing its exhaust gases into the secondary cylinder, so it would meet resistance and sap power.

Because the engine is working the air and fuel twice it would need a much larger turbo to be effective. For me this raises more questions than answers.

Colin

Give us a chance, I haven't worked out all the details, it was more a thinking out loud interesting possibility thing! I can't see how you can run an engine with that much back pressure.

 

[tomsutton529]

Isn't that the same way the T-Spark Alfa's work.. With the T-Spark being for twin spark to ignite the remaining fuel but in one cylinder?

could be way off and the JD is jut setting in..

 

[rikrobson]

This looks to be a version of the Atkinson cycle. Back in the early days of IC engines various types and processes were invented. The Otto Cycle we know today has stuck and apart from Wankel engines and a few prototypes not much has changed. The Atkinson process uses the fact that the gases can expand and therefore do more work more than they are allowed to in the Otto cycle. Modern engines that are used in hybrid vehicles keep the inlet open longer and allow fuel air to pass back into the induction manifold and therfore induct less for the volume of the cylinder. thus allowing the further expansion of the exhaust gasses. Older Atkinson designs used a secondary motion to allow for the further expansion of gasses. This process uses a separate cylinder
https://en.wikipedia.org/wiki/Atkinson_cycle