Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Researchers at Michigan State University recently invented the Wave Disk Generator that is supposed to get 60% fuel efficiency. What allows it to be so much more efficient than a traditional Internal Combustion Engine?

I am aware that there is better mixing of fuel and air, but surely this alone does not produce the extreme efficiency.

share|cite|improve this question
Just from the fact that they are not talking about using it as a direct power system you can bet that it runs well under some constrained set of conditions, but a hybrid arrangement allows it to always run under optimal conditions. That's where most of the gains in a standard reciprocating-internal-combustion--electric hybrid come from, but it seems this will can do better. – dmckee Apr 10 '11 at 23:35
That makes sense, since they are talking about developing a high-rpm generator to work with it. – Dale Apr 10 '11 at 23:50
@dmckee , even when running under optimal conditions a conventional gas engine will not exceed about 20, maybe 25 % . Trueborn Diesel engines achieve about 35 % – Georg Apr 11 '11 at 10:31
Let me just point out that rotary engines, on which this design appears to be based, have been around for a long time. Muller's et al's great innovation appears to be the addition of the serrated rows in the base of the rotors which compress the air-gas mixture more efficiently. Of course, there are probably other subtle changes that I fail to notice. Point being, Muller's engine is nice but a modification of a previous framework, not an invention per se IMHO – user346 Apr 11 '11 at 11:56
The better internal combustion engines are better than people think here. The Prius gasoline engine is reported to be 34% efficient. Large marine diesels can do 50%. – Omega Centauri Apr 11 '11 at 13:35
up vote 3 down vote accepted

That Prof Müller said it: Shock waves in addition of the usual things.

The picture in Your link is rather different from the thing shown in the video, for the time being, I do not understand really what is the new thing. From thermodynamics it is clear, that they (hope?) to have a higher effective DeltaT, obviously without having higher temperatures at machiney parts (which makes them expensive and/or short-lived)

I assume that those shock waves can be transformed into working pressure without the high temperatures of the combustion shock wave touchng machine parts. I hope we will hear more from Prof Müller in near future.


This link is somewhat more detailed and less press-release-silly. in general it says what I surmised (by application of thermodynamics basics)

share|cite|improve this answer

I found a link that explains it nicely.

share|cite|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.