Paul,

Can you direct me to the article or post on turbo compounding using
electric generator to drive a DC motor connected to the E-shaft method. While the conversion losses may be higher then that of a direct
drive via speed reduction unit, it would appear that the electric
method would be fairly easy for the home builder to put together.

Thank you
Rick.


Here are a couple of papers from the DOE on the Caterpillar program.

Paul Lamar


Paul,

Thank you for the documents on electric turbo compounding.  Of course my interest
is in Turbo Compounding a 13b.

Given the available exhaust heat/pressure in on a 13BT what size generator
and what size crankshaft motor would you suppose is needed to recover any excess energy?
What would you guess the mechanical/electrical/thermo losses might one
see a rotary setup? (in terms of %)

What sort fuel efficiancy would you guess/estimate can be realisticly
gained from such a setup on a 13BT?  I know that these are all very
vague questions but I'd like to get an idea of the "ballpark" figures.

Do you have any off-the-shelf turbos that would be suitiable to modify
and incorporate into a turbo-compund application?

Overall I can see why you are so passionate about turbo-compounding,
I too ask myself if it such a great thing then why hasn't anyone put
it into wider use? --Although I am guessing that the answer to this
question is more complicated then the technical challege of putting
together a practical Turbo Coumpound system together.

Thank you
Rick.

50 HP recovered is about doable on a two rotor. However an electric solution
means you will throw away about 10 HP of that or 20% not to mention the severe
weight penalty.

I think a 15% improvement in BSFC right off the bat with an all mechanical system
is very doable.

As development progressed we might see as much as a 25% improvement down
the road.  It also depends on the altitude and the duty cycle.
Aircraft engines will see the most benefit.

We just can't go on throwing away 50% of our gasoline out the exhaust
pipe of our internal combustion engines.

The turbo with the most potential is a Borg Warner used on Porsche's
with a variable area nozzle.

Paul Lamar