>> This is what it will look like more or less.
>>
>> The flange is about in line with the water pump front surface for
>> and adapter bracket off some water pump studs or bolts. This will
>> be the main mounting method.
>>
>> If this works as well as I think it will work it will drop
>> the rotary BSFC from .47 to .375 at about 14,000 feet. Better
>> than most diesels. Not bad for an additional ten pounds over
>> the turbo model.
>>
>> -------------------------------------------
>>
>> I had to shorten it to fit. There is only six inches between
>> the intake of the turbo charger and the front of the e-shaft
pulley.
>> I may have to machine some off the intake tube on the compressor.
>> I could probably get another inch of clearance between the back
of the
>> traction box and the turbo charger air intake area by that trick.
>> The 3/8th input shaft is now only about 2 or 3 inches long.
>>
>> Consequently the spacing on the traction box output shaft
bearings is
>> less than ideal but it will work for the prototype. The side
load or
>> tension on the belt is only about 105 pounds with 50 HP out at
>> 10,000 RPM shaft output speed.
>>
>> HP = RPM x Torque / 5252
>>
>> HP x 5252 / RPM = Torque
>>
>> Torque = 26 foot pounds or 315 inch pounds.
>>
>> Side load is therefore 105 pounds on a three inch pulley
diameter.
>> Output shaft bearings are rated at 1700 pounds so it should be
OK.
>>
>> Unfortunately the off the shelf multi V belt pulley is not
recessed.
>> A longer traction box snout could be designed with an off set
pulley
>> like the Mazda water pump pulley allowing more bearing spread.
>> A project for the future after we get some dyno data with this
setup.
>>
>> Some of the guts are missing from the planet carrier to show more
>> details in this 3D.
>>
>> -------------------------------------------
>>
>> I am slowing coming to understand that ideas are worthless
>> unless you can show that they fit using 3D drawing programs :)
>>
>> Notice the tight space between the drive and the turbo.
>> I know Gordon is going to say I told you so. "You should
>> have put the drive between the turbine and the compressor." :)
>>
>> I still think this can be made to work without the can of worms
>> of putting the traction drive between the turbine and the
compressor.
>>
>> I also still think I can machine the compressor intake down
about one
>> inch
>> and add a bell mouth to enhance air flow into the compressor.
>>
>> You always wanted a turbine engine in your car. Now is the
chance.
>> The Mazda Wankel makes an excellent gas generator for a turbine
engine.
>> Paul Lamar
stephen wolpin wrote:
> paul,
>
> nice drawings. rhino is cool.
>
> at 100k rpm, how does the 3/8 input shaft relate to the
compressor shaft
> and how will you assure they are aligned?
>
> i notice the nose piece on the traction box is long while the rear
> bearing area is short; is this necessary? why not move the box
toward
> the green drive pulley some? i realize that lengthens the shaft,
yet it
> also allows more room for inlet and rear bearing area.
>
> you could have a fwd cage around pulley for the front bearing so
pulley
> is not cantilevered, if that helps in the side load department.
>
> when do we hear it run?
>
> steve
Short piece of silicone rubber hose? :) Tiny U joint? :)
Lets see 50 HP at 100,000 RPM
HP = Torque x RPM / 5252 Torque is 2.6 foot pounds or 31 inch pounds.
There is a moment on the shaft because the pulley center is off
set from
the last bearings Consequently we need a little bearing spread in
there
to take moment. The moment is about 50 inch pounds.
These traction drive boxes are basically one big roller bearing so
the input
shaft is self aligning. There is no bearing in the back cover.
Just an oil seal. The outer ring is a spring.
http://www.nastecinc.com/traction.htm
http://www.rotrex.eu.com/
It will be after Sun n Fun before we can get it on the dyno at
Mazdatrix
as I have to be there for a forum on the subject.
http://www.mazdatrix.com/
Paul Lamar ...No rotor no motor.
The Rotary Engine NewsLetter. Powered by Linux.
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Copyright 1998-2006 All world wide rights reserved.
Paul,
Nice work on the latest drawings.
No, I'm not going to bug you anymore about where to mount the box. I
think you've got enough on your plate for now.
Anyway, it's a very nice setup and I'm keeping my fingers crossed
that
it works as planned.
Regards,
Gordon.
PS: Thanks for that CD, it arrived today and I'm just about to
crack it
open.
Your welcome Gordon. How about writing a turbo compound article for
EAA Sport Aviation or Kitplanes magazine. Your a good writer and
the turbo compound needs more exposure.
Heck why stop there I think the Wall Street Journal would also be
interested
due to its economic implications..
Paul Lamar ...No rotor no motor.
Paul,
If you can get this baby to work I will pitch the story to every editor
I know.
A turbo compound rotary engine for light planes that combines light
weight, reliability, and unmatched fuel economy is actually pretty big
news any way you slice it.
If a grassroots effort like your's and Doug's can beat the pants off the
big industry players...well, that's going to make for quite a story.
Regards,
Gordon.
------------------------------------------------------------------------
It will work no doubt in my mind.
We knew the wing would work on a race car long before we built one
and tried it. It took General Motors 65 years to get
around to trying it in an effective way. Same with the 2J sucker car.
Besides that thousands of R3350 turbo compound engines were built and
flew for years in half a dozen airplanes. You could start the story
with a bit of that history.
It just has not occured to Mazda yet as far as I know. They are the
only company in a position to exploit it as all others will be stymied
by the exhaust valve. It is only practal on the Wankel rotary.
The history of the R3350TC proved that.
Here is the traction drive cut away. There are no less than four bearings
and two one way clutches in that little box. Three ball bearings (green)
and one needle bearing (blue). The clutches are red. All the bearings
work
in conjunction to align the planet carrier with the case and the output
shaft with the planet carrier and the case.
The whole works is held together with one snap ring on the inner end of
the shaft and a clamp style hub for the output pulley. The big ball
bearing
is running at 12,000 RPM near it's limit of 14,653 but the load on it
is real
low compared to its rating of 2,400 pounds. The small ball bearing
and the
needle only see a few thousand RPM when the engine is over running the
turbo charger. When the turbo charger is contrbuting torque to the
core engine
these bearings are stopped. Both are way over designed.
The medium sized ball bearing takes most of the belt shear loads
and some of the belt moment. All the other bearings enter into
resisting the 50 inch pound belt moment but the loads are
very low. This belt moment will go away with the right pulley design.
Down the road.
This is not counting th six high precision roller bearings on the
rollers.
The one way clutches are rated at 36 HP each so two gives
us a safety margin of + 22 HP.
As you can see those one way clutchs complicated the design greatly
but I think they are essential. Don't leave home with out them.
BTW there is an interesting trick in the planet carrier. The sockets
that accept the ends of the roller shafts are over size ovals so
the rollers are free to move radially inward to clamp the input shaft
under the influence of the outer ring spring. Perhaps there is a patent
there if I were into patents :) Oh the wonders of NC mills!
My courses in machine tool programming helped me immensely when
it comes to mechanical design.
It is amzing that this tiny mechanical watch like device has the
potential to drop the turbo Wankel BSFC from .47 to .375.
Paul Lamar ...No rotor no motor.
paul,
i love your enthusiasm about this.
i'm still not clear how you intend to connect to the 100k rpm compressor
shaft and be in alignment with it. this seems super critical to me.
the two assemblies -- turbo and traction box -- need to be as-one and
aligned [with a viable air intake between them]. doable,.. how are you
planning to address that?
steve
The ultimate would be a one piece aluminum casting incorporating
the compressor housing and the traction drive housing.
Then the input shafts can be line bored. This is a prototype
designed to be bolted to the engine in line with the turbo charger.
In the mean time I will uses a short section of -3 or -4 SS braided
Teflon lined AN hose crimped in place :)
Paul Lamar ...No rotor no motor.
The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site.
http://www.rotaryeng.net
Copyright 1998-2006 All world wide rights reserved.