Has anyone done work on turbo-compunding these rotary engines? Should have similar effect as turbocharging without the
problem of high exhaust back pressures.


Wesley Butterfield

Not yet but we are getting closer.

http://www.rotaryeng.net/sum-turbo-comp.html

http://www.rotaryeng.net/Oxford-640-4802.wmv

http://www.rotaryeng.net/turbo-compound.html

We are getting closer to installing a DD15 truck engine turbo compound system
on a 3 rotor engine.

"At the rated engine speed of the DD15, the turbine reaches a rotation speed of more than 40,000 rpm. Power is
transferred to the gear drive, and therefore to the crankshaft, via a shaft and a hydrodynamic coupling. This
arrangement produces a uniform and smooth crankshaft rotation despite the higher torque, according to the company;
additionally, fuel consumption is reduced by up to 5 percent compared with a similarly spec’d Series 60."


I found a local Detroit Diesel repair shop and actually saw
the real thing. The shop is called "Big T's" 805 983 2408

<http://www.bigtsftln.com/default.htm>

They kindly gave me some part numbers with prices.
These engines are lasting up to a million miles so used
parts are in short supply. If you are lucky you
might be able to find one out of a truck wreck if the engine itself
was damaged. If the engine was OK I am sure somebody would pay big bucks
for it. Word is out. These engines are in high demand.

We just need the waste power turbine and gear box.
Any Mazda 20B turbo charger will work. Maybe even the stock sequential
turbo version which I have in the hangar will work.

All we need do is demonstrate a 5% or 10% improvement in BSFC
and the world will beat a path to the Wankel rotary door.

I'll kidnap the Mazda engineers here in SoCal and force them
to look :)

30% better BSFC is theoretically possible due to the lack of exhaust
valves in the rotary and that would be a revolution in internal combustion
engines.


This thing would easily replace a 600 HP turbo prop and have half
the fuel burn.

Paul Lamar

Paul,
What if you could add the turbo-compounding without the extra turbine weight and reduction gearbox. What if it also acted like a muffler? Got your attention yet?

Another new fuel saving and power enhancing scheme for diesels and the new generation gas engines is the use of
cooled-EGR. With an existing turbo you cool a portion of the exhaust gases via the wastegate/boost controller and
reinjest the mixture into the engine. The throttle must be opened more to acquire the necessary oxygen (dropping pumping
losses) and boost can go up but heat produced goes down.

The rotor has become the the mechanism for the compounding power. You would run 20psi boost on 10psi fuel maps. Ideally we could run throttle-less.

Here is an interesting GM study.

https://docs.google.com/file/d/0B_jE2-IDoVTfb1RiWEs0ZmJCaDQ/edit?usp=sharing

Barry Bordes

Dave Leonard flies a turbo II 13b without a muffler.

All diesels run with wide open air throttle. There is no air throttle.

Paul Lamar

Paul, let me try this from another angle.

Instead of thinking of a rotary engine with a turbo.... think of it as*Turbine Engine *using the rotary engine as the power turbine section with gear reduction.

This new turbine engine eliminates the expensive fuel control, burner section, and gear reduction normally needed for turboprops.

The historic problem has been the rotary's high EGT which limits output. This now can be mitigated using Cool-EGR like a compressed inert gas helping to spin the rotor for free.

More HP than a three rotor, plus less weight, plus half the BSFC.

Barry Bordes

I see only an increase in the size of the best BSFC island. Any amount of torque
is available with the right gearing and an infinitely variable gear ratio. Not mentioned in the pdf. Cars accelerate on HP and not torque. All and all a narrow minded paper based on a bunch of incorrect assumptions .

Also I see no charts where EGT is a parameter.

All this is political based on the sky is falling erroneous assumptions that we are going to  run out of oil. I was around in 1973 when the water melons
were saying we were going to run out of oil in 1990. Now we are swimming in oil
partially due to Fracking except the stupid water melons won't let us build a pipeline. The answer is eliminate the moron water melons that want to burn food for fuel.

Paul Lamar


The Rotary Engine News Letter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
You Tube http://tinyurl.com/beqqxas
Copyright 1998-2013 All world wide rights reserved.