"The exhaust heat warms the air that comes into the engine before the fuel is added [see illustration, below]. This hot air leads to more powerful combustion, which means the StarRotor can extract more energy from a given amount of fuel than a conventional engine could."
While heating intake air increases atomization (Richard Petty), thermodynamically you want cold/dense air coming in. Otherwise supercharger intercoolers wouldn't be used. Add to that the seal problems.
Not saying it won't work (yet), just saying your milage may vary somewhere less than utopia.
On further inspection, I see they are judt running a recuperator. You could do the same thing by taking a V8, using 4 pistons for compression and 4 for 2 stroke combustion with a recuperator. You'd end up with the same problem, one hell of a lot of heat.
That's exactly right and what I thought when I started reading this.
But if you go to the website you find out that the fuel-air mixture is heated after the compressor stage. Makes a little more sense now.
I thought the same thing at first, but their design appears to be heating the air after the compression phase, so that shouldn't be an issue. Not sure about the thermodynamics of it, though presumably they have thought that through. I suspect the shortcomings of the engine will be in the practical details - materials, durability, range of speeds for efficient operation, and so on.