[mamelukesabre]

Detroit Diesel has taken a WWII fighter plane technology and applied it to semi truck engines to enhance fuel economy and power.

Here's an explanation: http://en.wikipedia.org/wiki/Turbo-compound_engine

And the link again: http://www.layover.com/news/article/detroit-diesel-dd15-engine-turbo-compounding-wins--15127.html

[truth_seeker]

Audi used Turbo-diesel technology to win several LeMans races.

Puegot won with turbo-diesel this year.

Nothing new here, except the possible popularity for passenger vehicles in the US big IF the government will allow it.

VW’s Jetta TDI is a 2.0 liter engine, which gives 29 mpg city and 40 mpg highway.

[doorgunner69]

Detroit Diesel has taken a WWII fighter plane technology and applied it to semi truck engines

That was my instantaneous thought when I saw the thread title.

[Pontiac]

The PRTs (Power Recovery Turbines) recovered about 20 percent of the exhaust energy (around 500 HP) that would have otherwise been wasted, but unfortunately had a negative effect on engine reliability, causing many aircraft mechanics of the day to nickname them "Parts Recovery Turbines" (and worse)

Increased complexity often equals increased maintenance.

[Nathan Zachary]

Not a very good explanation.

Truck diesel engines are already "blowdown" type turbochargers, they don't use superchargers driven by the crankshaft as this wiki article suggests.

Apparently this "compound turbocharged engine" is just a method of using several turbochargers to increase pressures without increasing intake air/fuel flow.

Trucks with a single turbocharger are already running boost as high as 30 lbs, and when pulling a heavy load up steep roads engines are getting pretty hot as it is. Adding more boost will only make those combustion chambers and exhaust gases leaner and hotter.

That's probably the reason why Detroit diesel never got past the development stage with them.

[Nathan Zachary]

Maybe by using compound turbochargers provides a way to get rid of some of the heat that single turbochargers create in boost air. The more heat you can get out of the air the better. The engine will run cooler and more efficiently, and have more power because the air density will be higher.

[Niteflyr]

An early example: a turbo-compound engine collects all of the exhaust gasses and runs them through a turbine, with all of the power generated going back into the crankshaft and ultimately to the propeller. It differs from a turbo-supercharged engine, which uses exhaust gas energy to increase the pressure of incoming air. Work on this particular engine began in about 1944 and continued until 1946, when Allison asked that it be canceled because turbine engines had greater promise.

Allison V-1710

[Getready]

Just sounds like the exhaust gases drive a turbine which is hydro-
dynamically connected to the drive gears..using waste energy
to help drive the wheels...decent idea.

I suppose this could work with a gasoline engine also. Anyone know
about that ?

How about using the waste heat to power stirling engines which
help recharge batteries in a hybrid?
I wonder if anyone has ever tried this combination:

Hybrid Car
High pressure(higher than normal diesel in diesel system)
and same in gas engine
Solar cell array on roof,trunklid, engine hood to recharge batteries.
Stirling engines to recover all waste heat(exhaust, cabin temp)
to recharge batteries
Superoverdrive transmission
Low final drive ratio
Super low coefficient of drag
I wonder if they could apply such considerations on the
new Volt.
Anybody here with a car engineering degree who would know
about these things?

[Pistolshot]

Ok, but will I get more chicks?

[taildragger]

Folks, if you do not know who Paul Lamar is go here....

http://www.rotaryeng.net/

He has been a quest for a while to Turbo-Compound a Rotary (Wankel).

His reasoning is the CW-3350's had issues with the exhaust valves. Rotaries do not have exhaust valves.

Check this page out as well: http://www.rotaryeng.net/turbo-compound.html

Also.....

Check this out, Pratt and Whitney Canada's Application for a Patent...Turbo-Compounded Rotary

http://v3.espacenet.com/publicationDetails/biblio?CC=EP&NR=1611331&KC=&FT=E

[mamelukesabre]

http://www.youtube.com/watch?v=iy_Jd5kewbM

http://www.youtube.com/watch?v=WOtQG35EK_s&NR=1