Parallel Diesel/Stirling hybrid?

[pistonhead76]

Hey everyone. I have a lot of downtime at work and watched a bunch of videos on the Stirling engine. This thing is quite interesting. I googled it and there have been some commercial applications but mostly home experiments. I had an idea which Im sure is not original. If you had a lightweight rwd vehicle with a parallel hybrid drivetrain (small diesel engine, trans, elec motor, rear axle) you could plumb a large stirling engine into the exhaust stream. Obviously taking necessary steps to keep the heat in the exhaust pipe via wraps and insulation and having the head of the engine directly in the hot exhaust gas stream. The stirling would be connected to a gen head which would charge the batteries. Im wondering if recapturing this waste heat in this matter would be worth it. This would probably have to be a small truck with the gen setup in the bed. Thoughts please.

[Frank Lee]

Gains would have to be worth the cost, complexity, volume eaten up, and weight.

[elhigh]

Exhaust is hot, but is it hot enough? I'm not smart enough to have that kind of math in my head, but if you want decent power out of a Stirling, it's all about the delta-T. Lower temperatures require larger heat exchangers, larger displacer pistons, and generally lower revs. You might wind up going backward in terms of efficiency.

It might be easier to just stick a hundred Seebeck devices onto the exhaust pipe and obviate your alternator.

[P-hack]

Here is a pretty cool sterling RC car, you can see though that it is pretty bulky and weak.

http://www.youtube.com/watch?v=LFTt7Jd5450