D13 compounding turbos

The d13 automation video drives the "turbo" from a set of gears off of the crankshaft. Maybe I'm missing the using exhaust waste idea in it somewhere?

 

I'm thinking, it's using a twin induction system, which uses a supercharger and a turbo.

 

Yup you are wrong.
Turbo 1 exhaust drives turbo 2 who drives the gears and thus the cranckshaft .

 

Bingo, exactly.

 

turbo compounding was common during WW 2 on the big radials ,hundreds of hp shafted to the prop.
google wright-curtis turbo compound....... then jets came and it was over

 

And why?

 

recover wasted power
result better mileage ..... within a narrow rpm range

 

It makes no sense to me whatsoever that a turbo adding compression to another turbo then using a gear drive to send the extra power to a crankshaft would even make a difference. That's quite a conflict.
It makes more sense to use twin induction, which I believe is what it's doing.

 

It's physically using the secondary turbos output to mechanically link to the drive input shaft and increase mechanical power being delivered to the driveline.

It does not compress, blow or otherwise in any way influence the intake pressure of the engine.

All it's doing is increasing the use efficiency of the waste gasses because an impeller driven off exauhst gas can only return to much of the energy used to spin it. I've never actually checked turbo efficiency returns but I'd bet dollars on it being lower than you expect. Adding a supercharger would also not likely be as efficient as compounding the wasted momentum of a turbo not spinning air into the engine (hence the flywheel in turbo compounding) and physically, mechanically adding it to the driveline through a series of high torque to low rpm reduction gears.