THE COMBUSTION ENGINE REIMAGINED

[Bikeman315]

Anyone ever hear of this? Thoughts!

https://invest.liquidpiston.com/?ut...ship42-01_03-31&tnames=partnership42-01_03-31

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[Balr14]

That bears a strong resemblance to the Wankel engine. We all know how well that went. This shows improvements to that original concept that might overcome major flaws (high rotor tip wear, no torque and poor fuel mileage). It would probably be more applicable to small engine applications. I had a friend who had an RX7... I swear that thing didn't have enough torque to stir thick paint.

 

[Skye]

I was thinking torque as well and also oil consumption? Isn't one of the reasons Mazda shelved the Wankel was lack of oil control? Unexplained oil loss, sometimes in large amounts.

 

[Balr14]

I was thinking torque as well and also oil consumption? Isn't one of the reasons Mazda shelved the Wankel was lack of oil control? Unexplained oil loss, sometimes in large amounts.

A lot of oil consumption was attributed to rotor tip wear, some was attributed to cavitation, but they didn't really have a clue.

 

[Strokerswild]

Interesting take on the Wankel. On those, the apex seals on the piston wore quickly, which was a main cause for oil consumption. They mention stationary seals that can be lubricated directly on this variant, which might be the key to it working well.

Wankels definitely aren't torque monsters (especially at low speed), but proper gearing can make up for that. One thing they are is smooth.

 

[Oakley]

that's just a rotary engine with the apex seals mounted to the block instead of on the dorito.

its literally just an inverted rotary engine.
rotary engines suck because they are flawed in principle.

whoever gives to that is an idiot.

 

[Hack]

It's possible that putting the seals on the outside could be a huge improvement.

However, if it worked they wouldn't need your money. They would be making money hand over fist.

 

[Oakley]

It's possible that putting the seals on the outside could be a huge improvement.

However, if it worked they wouldn't need your money. They would be making money hand over fist.

not if you understand why the seals fail. the design is fundamentally the same as a rotary engine the dorito is just shaped like a peanut now.

the same surface that needs oil also endures combustion, therefore, it will eat oil, have crappy mileage, and probably doesn't make more power.

 

[Hack]

not if you understand why the seals fail. the design is fundamentally the same as a rotary engine the dorito is just shaped like a peanut now.

the same surface that needs oil also endures combustion, therefore, it will eat oil, have crappy mileage, and probably doesn't make more power.

It's easy to understand why seals in a Wankel fail. What is difficult to understand is why piston rings in a reciprocating ICE live for hundreds of thousands of miles.

I don't think the seals ride against the combustion chamber areas in a Wankel.

 

[Oakley]

It's easy to understand why seals in a Wankel fail. What is difficult to understand is why piston rings in a reciprocating ICE live for hundreds of thousands of miles.

I don't think the seals ride against the combustion chamber areas in a Wankel.

well first off, you have more than one ring per piston and each one does a different thing.
you seal off the combustion process from the oiling process.

in rotaries you get one big fat seal and its constnatly riding on surfaces that explode and get oiled.

that's why piston engines dont use oil if all is well and rotaries drink it like gas lol

 

[Hack]

well first off, you have more than one ring per piston and each one does a different thing.
you seal off the combustion process from the oiling process.

in rotaries you get one big fat seal and its constnatly riding on surfaces that explode and get oiled.

that's why piston engines dont use oil if all is well and rotaries drink it like gas lol

I agree having an oil scraper and two rings must help, but that geometry could be built into a Wankel. Probably having reversing motion helps in some way and also having combustion pressure push the rings to provide sealing helps as well. Do you know how the velocity of a seal in a Wankel compares to the maximum velocity of a typical piston?

Remember that in piston engines the combustion doesn't only occur while the piston is at TDC. The piston gets well down the bore and combustion gasses and by products like soot cover the cylinder walls.

 

[Oakley]

I agree having an oil scraper and two rings must help, but that geometry could be built into a Wankel. Probably having reversing motion helps in some way and also having combustion pressure push the rings to provide sealing helps as well. Do you know how the velocity of a seal in a Wankel compares to the maximum velocity of a typical piston?

Remember that in piston engines the combustion doesn't only occur while the piston is at TDC. The piston gets well down the bore and combustion gasses and by products like soot cover the cylinder walls.

it can't work the same because the rotor never changes direction.
the fundamental design of the wankel is its Achilles heel.
it is a novelty not an advancement.

 

[Balr14]

it can't work the same because the rotor never changes direction.
the fundamental design of the wankel is its Achilles heel.
it is a novelty not an advancement.

Good point!

 

[ice445]

it can't work the same because the rotor never changes direction.
the fundamental design of the wankel is its Achilles heel.
it is a novelty not an advancement.

I do have to point out though that in a sustained high load application, like racing, the majority of the shortcomings disappear. It's kind of like a jet engine in that regard, which is a thirsty pig at lower altitudes and gets much more efficient in the upper atmosphere. Much like rotaries suck balls for normal driving conditions, but on a race track under constant heavy load, they do much better.

So much better in fact, they got banned in LeMans over a displacement technicality lmao

 

[Oakley]

That doesn't negate the point at all. They essentially require special fuel and fail way faster than piston engines but at easier to work on. Those attributes make it not a bad choice for racing but doesn't change the fact that piston engines and turbine engines are vastly superior.

Racing just eliminates several factors that determine reliability in normal use, ironically enough .

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