I came across this site about the twin screw supercharger,
http://www.coloradocobra.com/whipple/about-whipple/whipple-twin-screw.html
which apparently has advantages over Roots and centrifugal superchargers.
I thought of how such a supercharger could be made to “run backward” , collecting and capturing pressurized exhaust from the manifold in a kind of non-turbo turbocompounding application.
Then it struck me…do away with the reciprocating engine altogether and bolt two whipples together with a combustor between them.
It is neither a diesel, nor a gas turbine, but has characteristics of both.
A true rotary engine.
Anyone have an idea why this wouldn’t work?
Hard to get combustion that forces the screws downward efficiently? How would the chamber be constructed so that the explosive energy acts to push a radius down? It needs to act agaist some surface/plane which is driven away?
Maybe make the screws more like paddles, so that the forces push down on the paddles, which interconnect to produce a flat plane of some sort…'cept that the flat plane is two interconnected screws with paddles on them.
Good luck with the timing!
I remember about ten years ago an engineer form a company called Trane came to carry out major maintenance on some large HVAC chillers at the hospital power plant.
He said that Trane had all the patents on this technology and it was going to be the ‘next big thing’.
Trane uses large versions of this device in its Cent-tra-Vac range of absorption units.
The engineer stated that these things could be made very small and yet they would be very efficient, and had significant advantages over turbos and superchargers and he expected to see them widely used in cars.
I cannot et yor link to work, but I have found one for Trane(they are a very large company) and if you contact them they would probably be able to answer your queries.
http://www.trane.com/Commercial/
I can imagine your idea, but although you have compression, you would also need an expension phase for the burnt expending gases, similar in principle to a jet engine.
I imagine there would be some upper limit for rpm that makes it less than useful compared to a turbine.
I would imagine that it would be hard to get a high enough compression ratio for the purpose you describe, due to the very close tolerances required the would be some problems with heat expansion.
Indeed, I figured this device may only produce a 3 or 4 to one compression ratio: we would need at least 10 to 1 CR to compete with standard IC engines.
Perhaps using multiple compressors in paralel or in series?
The exhaust “expander” could be made of ceramic: since the rotors don’t actually touch each other or the housing, there is no problem with lubrication or wear.