Paul,
The reason I like the Rotrex is because it's a fully developed product
and if it can be adapted in a simple solution that would save a lot of
R&D effort. If you could just mate that unit to a nice off-the-shelf
turbine, you'd be all set -- all you would need is a pulley on the
engine. A very simple and elegant turbocompound engine with minimum
fuss.
However, this does not appear to be easily doable.
Looking at the pictures I have of the Rotrex, it is obvious that the
pulley and the compressor wheel turn counterclockwise when viewed from
the front. I guess in order to install these in cars with engines that
turn clockwise, the unit would have to be turned end-for-end with the
pulley facing rear.
In order to mate this to a turbine wheel, the turbine shaft would have
to go in through the pulley side. The only way this could be done is to
hollow out the pulley shaft (which is also attached to the annulus drive
ring) and have a common shaft going straight through. This shaft would
support the turbine wheel and the compressor wheel and would also be the
sun shaft for the gearbox.
The turbine would be on one end, then the gearbox in the middle and the
compressor on the other end, with that inlet facing forward
unobstructed.
Obviously this would require substantial modification of the Rotrex unit
in order to accommodate this shaft. A hole would have to be drilled in
the pulley end of the gearbox housing for the shaft to pass through and
some way of sealing that hole to the shaft in order to prevent oil
leakage. Plus you would have to make a suitable shaft.
Regards,
Gordon.
The traction drive is not as hard as it looks.
I have a lot of experience designing mechanical things,
building them and making them work. The principle
is hundreds of years old. There is a another company that will
deliver a unit to our exact requirements.
I feel largely responsible for Doug buying the Rotrex in the first
place.
Sorry Doug.
Unfortunately I was at first suckered into the Rotrex thing
due to their clever publicity and a smoke screen patent they where
granted by some incompetent patent examiner.
After Doug got the unit it turned out there was absolutely no new
ideas in the unit and the patent had absolutely nothing to do
with the way it actually worked. Similar devices have been available
off the shelf for years. They merely copied some one elses product.
So much for a fully developed product by Rotrex.
I was too ignorant to know about this company that Dale Mahan
on here discovered. Thanks Dale. Here is his actual message.
"Subject: Traction Drives
Date: Fri, 17 Feb 2006 09:13:47
From: Dale Mahan
To: Rotary Engine "
"Hi Paul,
What do you think about a traction drive being used as as a PSRU?
The Nasvytrac drive has been with us for decades, originally designed
as a helicopter turbojet to main rotor powertrain component
(
http://www.nastecinc.com/traction.htm)."
Lately, some of the diagrams that have been shown on the Rotary Engine
group look like they may be able to offer a low cost alternative to
planetary gears. Sometimes, the PSRU costs about as much as the engine
itself.
Thank you,
Dale Mahan"
Here is an excerpt from their web site.
http://www.nastecinc.com
"Nastec, Inc. is a Cleveland, Ohio based designer and manufacturer
of specialty transmissions and bearings. During the past twenty years,
we have established ourselves as one of the world's technical leaders in
the design, fabrication, and manufacture of traction drives, roller-gear
drives, and wave bearings."
I'll get a quote from them on Monday.
If I were Doug I would sell the Rotrex unit to someone that
needed a supercharger instead of kludging it up to make it
work.
Paul Lamar ...No rotor no motor.
Paul,
thanks for that link to Nastec. Interesting looking traction drives, but
there is virtually no info on their website.
I agree that a roller-type friction drive is a pretty simple device --
at least on its face. However, there are lots of details to work out,
like a suitable lubrication system, etc. Maybe that Nastec unit will be
just the ticket.
I have no doubt that you are capable of designing and refining a
perfectly good traction drive. I'm well aware of your distinguished bio
and and I think if anyone is going to do this successfully it will
be you.
Looking at the drawings of your traction drive design, it looks like the
whole planet carrier is going to spin, correct? Isn't that spinning mass
with the rollers included going to generate a fair bit of moment? This
would have something of a flywheel effect I would think, and some
inertia for the turbine to overcome as it's spooling up.
Regards,
Gordon.
--------------------------------------------------------------------
You know the power in the exhaust has been talking to us for 30 years.
It has been saying. "Hook me to turbine, hook me to a turbine, hook
me to
a turbine." Anybody that has been around a Mazda rotary powered race car
without a muffler can understand the tremendous kinetic energy in
the exhaust.
I have a race car driver friend by the name of John Morton who claims he
has permanent hearing damage from driving rotary powered race cars.
It was not until I read that SAE paper on the R3350 TC that I could put
a number on it. It then hit me like a supersonic shock wave. Yes of
course it has plenty of kinetic energy in the exhaust.
Now comes the time to harness all those super sonic horses :) (Sorry JD)
Think of the Wankel rotary as an ideal gas generator for a turbine
engine. A marriage made in heaven.
To answer your questions Gordon. Yes the whole planet carrier
spins at the output shaft speed of 12,000 RPM max. Yes on the moment
but compared to the 160 foot pounds of torque from the engine it
is inconsequential. Think of the flywheel and the clutch. For the
turbine alone however it would not be inconsequential. It is a good
thing we are not concerned with turbine acceleration for an aircraft
engine.
The traction fluid is available at your local Ford and Nissan dealer
as they use traction drive CVT automatic transmissions.
Paul Lamar ...No rotor no motor.
Well said, Paul.
The rotary is indeed ideal for spinning a turbine with its prodigious
exhaust energy. And it gets better with altitude, so much more so that
there is much much more power available than a turbocharger could use.
Why waste that power? Why not put it back in the engine?
The turbocompound rotary is going to open a lot of eyes very wide...
Regards,
Gordon.
Thanks Gordon.
BTW I shipped the CD off today with the SAE TC paper.
Paul Lamar ...No rotor no motor.
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