Did any of you read about the new Cummins steam augmented engine? It uses a closed steam system to run a turbine that runs a generator which is connected to an electric motor integral with the crackshaft. Apparently it saves 10% fuel consumption. The article is in October's Diesel Power mag. Check it out!

 

Is it a co-gen setup, where the exhaust heat generates the steam for the turbine? Seems like you'd lose a lot of power driving a generator to power a motor, although you'd need to keep the turbine RPM up, so direct shaft coupling wouldn't work as well.

 

Yes, exactly. I guess the losses don't matter since any energy recovered this way is a plus.

 

You said Crack Shaft

 

Eeeek! Freudian slip, or subconscious drug connection to the subject. Hmmm.

 

Either way, I think we need to stage an intervention!

 

Here's the schematic compliments of the Department of Energy (DOE).

 

Iveco has a system that is used on some of the larger Steiger tractors (atleast with New Holland paint on them) that is supposed to scavenge off heat and pressure from exhaust gasses after the turbo and runs a small torque converter like device which is coupled to the crank via the timing case (opposite side to the timing gears I believe) an is supposed to save fuel an increase power.

 

Volvo runs a turbine in the exhaust system as well that runs on the crank gear.. Supposed to add another 50 hp.. The Co-Gen sound neat for a stationary use unit, I have doubts on the open road..

 

I was amazed when I read that. I actually thought about that a while back in my head but didn't think I'd see it in an actual mass-produced engine anytime soon! It makes so much sense. All that heat emitted from an engine is just wasted energy. We're able to gain some of it back through the form of a turbo, why not more?