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LiquidPiston – The combustion engine reimagined

invest.liquidpiston.com

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Re: LiquidPiston – The combustion engine reimagined

#3

Post by stefncb »

canbus wrote: post #2

hmmm.. still uses apex seals, would need seriously small tolerances to make it work effectively. Call me skeptical but I don't see how this is really any better than the traditional wankel/rotary design

It's effectively an inside-out wankel, so the seals are stationary. This is a much easier problem to solve, and now you don't need to throw oil in the combustion chamber to lubricate the moving seals.

Re: LiquidPiston – The combustion engine reimagined

#4

Post by drcongo »

stefncb wrote: post #3
canbus wrote: post #2

hmmm.. still uses apex seals, would need seriously small tolerances to make it work effectively. Call me skeptical but I don't see how this is really any better than the traditional wankel/rotary design

It's effectively an inside-out wankel, so the seals are stationary. This is a much easier problem to solve, and now you don't need to throw oil in the combustion chamber to lubricate the moving seals.

Thanks both, I'm not very mechanical and came to the comments to find out what makes this not a wankel.

Re: LiquidPiston – The combustion engine reimagined

#5

Post by chipsa »

canbus wrote: post #2

hmmm.. still uses apex seals, would need seriously small tolerances to make it work effectively. Call me skeptical but I don't see how this is really any better than the traditional wankel/rotary design

It inverts where the apex seal goes. So instead of having it on the rotor, and hard to lubricate, it goes on the housing, which is much easier to lubricate.

Re: LiquidPiston – The combustion engine reimagined

#6

Post by rjmunro »

> Hydrogen may be generated by renewable sources such as solar energy, making it overall a cleaner alternative than batteries on a well to wheel basis

Err, what? I guess you could contrive a scenario in which the extra solar panels and equipment needed for generating, managing and storing the hydrogen was less "well" than the batteries for equivalent "wheel" output. Perhaps if you make infrequent but long journeys, so you need a big battery, but only a small amount of power generation, but hydrogen is a very inefficient way of storing electrical power, maybe 50% of the energy back compared to over 90% with batteries.

Re: LiquidPiston – The combustion engine reimagined

#9

Post by Cthulhu_ »

xnx wrote: post #8

Posts on Hacker News related to LiquidPiston go back 11(!) years. The most comments are on this post: https://news.ycombinator.com/item?id=25450477 If this was going to revolutionize anything, it would've happened by now.

I think any engine design that was popularized was backed by a car company, even the Wankel engine. If they want to make this design popular, they need to design products around it so their claims are proven.

I mean I still don't believe Tesla's primary business model is cars; the competition is outselling them left right and center. Theirs is batteries and charging infrastructure. That's a huge market that can fuel the company for a century if they play their cards right.

Re: LiquidPiston – The combustion engine reimagined

#10

Post by pfdietz »

rjmunro wrote: post #6

> Hydrogen may be generated by renewable sources such as solar energy, making it overall a cleaner alternative than batteries on a well to wheel basis Err, what? I guess you could contrive a scenario in which the extra solar panels and equipment needed for generating, managing and storing the hydrogen was less "well" than the batteries for equivalent "wheel" output. Perhaps if you make infrequent but long journeys, s…

Right. Hydrogen only makes sense for leveling over very long periods, and then only when the capital cost of the hydrogen storage tank is low enough (for example, storing it underground like natural gas is stored) so this can overwhelm the "cost of inefficiency".
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