Liquid Piston HEHC-Rotary out of the Dyno for first time.

I'm really struggling to get excited about this, and I love new engineering designs and disruptive technologies.

This just seems way to complicated for very little return.

Good luck to the developers but I can't see this evolving past a hobby project sadly. Hopefully I'm wrong.
 
Am I right in thinking that they are using ram air cooling through the rotor? If so they will face the same challenges as the air-cooled-rotor Wankel engines.

There is a reason that their working engine is only a 3 horse power unit, it will most likely cook itself in a larger unit without masses of air flow.

I find the new combustion cycle interesting but this is nothing new, there are many "new cycles" out there that look great on paper, but translating that into a working prototype that has any amount of durability is a different story.

Good luck to them anyway, they seem to be publicising it well (just hope they are in it for the long haul, rather than just the investment opportunities).
 
Diddums said:
I'm really struggling to get excited about this, and I love new engineering designs and disruptive technologies.

This just seems way to complicated for very little return.

Good luck to the developers but I can't see this evolving past a hobby project sadly. Hopefully I'm wrong.
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They already have 2 Million + in funding from DARPA.
 
rhyswt said:
Am I right in thinking that they are using ram air cooling through the rotor? If so they will face the same challenges as the air-cooled-rotor Wankel engines.

There is a reason that their working engine is only a 3 horse power unit, it will most likely cook itself in a larger unit without masses of air flow.

I find the new combustion cycle interesting but this is nothing new, there are many "new cycles" out there that look great on paper, but translating that into a working prototype that has any amount of durability is a different story.

Good luck to them anyway, they seem to be publicising it well (just hope they are in it for the long haul, rather than just the investment opportunities).
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They have already tested it and compared to petrol, diesel and other engines, it pretty much runs within a few percentage difference to the theoretical cycle.

it also runs far cooler compared to a normal petrol engines since the over expansion on the exhaust cycle helps to extract more energy from the fuel rather than it being wasted as heat.

each combustion chamber is only 23cc and there are three of them and all three have a combustion every cycle. it gets 3HP at 10k rpm and 5 at 15k while being 1/10th the weight of a comparable engine.

The diesel prototype was also an early proof of concept engine that ran far better than expected. And was only ever run over short periods, that is why it has no cooling system built in.
 
Mauller said:
They have already tested it and compared to petrol, diesel and other engines, it pretty much runs within a few percentage difference to the theoretical cycle.

it also runs far cooler compared to a normal petrol engines since the over expansion on the exhaust cycle helps to extract more energy from the fuel rather than it being wasted as heat.

each combustion chamber is only 23cc and there are three of them and all three have a combustion every cycle. it gets 3HP at 10k rpm and 5 at 15k while being 1/10th the weight of a comparable engine.

The diesel prototype was also an early proof of concept engine that ran far better than expected. And was only ever run over short periods, that is why it has no cooling system built in.
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Any more sources for further reading? I have many questions I can't see answers to on their website :D

Are they taking the exhaust gas back through the rotor? Any details on the lubrication system?
 
It's important to remember that the conventional internal combustion engine that we all know and love, has had 150 years of development. Unless there is a critical flaw in the concept of this engine (which I would hope there isn't given the knowledge and money involved) then why are we surprised that it isn't a ICE beater out of the box?
 
rhyswt said:
Any more sources for further reading? I have many questions I can't see answers to on their website :D

Are they taking the exhaust gas back through the rotor? Any details on the lubrication system?
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From the videos that i have seen there is over expansion on the exhaust but no exhaust gas recovery. i assume they don't need to factor it in with how clean the exhaust is. There was an earlier video that demonstrated the exhaust from the engine and there was no vapour or smoke from it, visibly it didn't even look like the engine was running.

Nothing that i can see about lubrication, but there was talk about only having to apply the right amount of lubricant to the chamber seals.
 
Gayjin said:
It's important to remember that the conventional internal combustion engine that we all know and love, has had 150 years of development. Unless there is a critical flaw in the concept of this engine (which I would hope there isn't given the knowledge and money involved) then why are we surprised that it isn't a ICE beater out of the box?
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Simply because people have been looking for 150 years and despite a huge number of attempts nothing so far has proven competitive in all areas. Many designs have promised to deliver better efficiency, lower emissions etc. but are almost always dogged by size/complexity/manufacturability/longevity/reliability issues.

I suspect Mazda spent an awful lot more money developing the Wankel engine than this one (so far at least) and that was hardly the saviour of the ICE.

Mauller said:
From the videos that i have seen there is over expansion on the exhaust but no exhaust gas recovery. i assume they don't need to factor it in with how clean the exhaust is. There was an earlier video that demonstrated the exhaust from the engine and there was no vapour or smoke from it, visibly it didn't even look like the engine was running.

Nothing that i can see about lubrication, but there was talk about only having to apply the right amount of lubricant to the chamber seals.
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There's always going to be water vapour in the exhaust of an ICE burning fuels containing hydrogen, and the exhaust of a correctly tuned conventional four stroke engine is also invisible.

I don't want to come across as negative because I truly hope that something like this can provide the boost in efficiency that ICEs need, but expectations need to be realistic.
 
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Dogbreath said:
Simply because people have been looking for 150 years and despite a huge number of attempts nothing so far has proven competitive in all areas. Many designs have promised to deliver better efficiency, lower emissions etc. but are almost always dogged by size/complexity/manufacturability/longevity/reliability issues.

I suspect Mazda spent an awful lot more money developing the Wankel engine than this one (so far at least) and that was hardly the saviour of the ICE.



There's always going to be water vapour in the exhaust of an ICE burning fuels containing hydrogen, and the exhaust of a correctly tuned conventional four stroke engine is also invisible.

I don't want to come across as negative because I truly hope that something like this can provide the boost in efficiency that ICEs need, but expectations need to be realistic.
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One thing to remember is that most of that 150 years of design has been using materials and testing/precision that is way out of date.
There are a lot of industries where things have been written off because everyone "knew" that something didn't work because it had been tried in the past, so most/all the experienced people just didn't consider that line of design any more and it becomes a "truth" that everybody "knows" that such an idea doesn't work with few people questioning it.
Then someone comes along with a new material, or the ability to make something more precisely and overcomes problems that stopped previous attempts early on.

I suspect with modern computer modelling, prototyping and materials it's possible to try hundreds or thousands of variations on a design for the time/cost of doing a few dozen a few decades ago.

I wouldn't be surprised if a more efficient ICE than the current mainstream designs came along from something that was tried and dropped decades ago because of material/production limitations.

Apparently there is something similar with the design of the blades for windmills and prop driven aircraft, a lot of the design for them is based on principles assumptions from the 1900's and early days of flight, I remember reading that some of the most advanced and efficient props were designed by a guy who basically ignored the accepted idea of the most efficient designs and went for something that looked completely different (and got a big increase in efficiency from that change in look).
 
Dogbreath said:
Simply because people have been looking for 150 years and despite a huge number of attempts nothing so far has proven competitive in all areas. Many designs have promised to deliver better efficiency, lower emissions etc. but are almost always dogged by size/complexity/manufacturability/longevity/reliability issues.

I suspect Mazda spent an awful lot more money developing the Wankel engine than this one (so far at least) and that was hardly the saviour of the ICE.

There's always going to be water vapour in the exhaust of an ICE burning fuels containing hydrogen, and the exhaust of a correctly tuned conventional four stroke engine is also invisible.

I don't want to come across as negative because I truly hope that something like this can provide the boost in efficiency that ICEs need, but expectations need to be realistic.
Click to expand...

of course, it is just a matter that the exhaust overall is cleaner etc, where as a lot of engines are not perfectly tuned so you often see exhaust smoke/vapour etc.
 
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