http://www.7tune.com/video-ppres-6-rotor-beast-is-alive/
Rob Woods
Paul it's not a slide throttle is it? they look like 6 butterfly's
to me. How would you keep the E shaft together, or can one be made in
one piece. Would windup be a problem
as "P" ported should produce 100 hp per rotor 500 hp at the last
rotor plus the extra from that rotor!!
John Burey
All good questions :)
A p-port will yeild 150 HP per rotor at 10,000 RPM if the shafts lives
:)
900 HP!
Paul Lamar
http://www.facebook.com/media/set/?set=a.388296644556315.103373.208088479243
800&type=3<
http://www.facebook.com/media/set/?set=a.388296644556315.103373.208088479243800&type=3
Rob Woods
http://www.hurleyrotary.com/page.php?currentpageref=6265
"After ten years of development HME are now proud to offer our
multi-rotor
engine
conversions, the first triple engine was built three years ago and has
been
tested by
many magazines in the United Kingdom, Europe and Australia, all of which
have been
impressed with the performance and fuel economy. To date 25 engines have
been built
for road and racing."
"The turbine smooth and refined performance of the triple rotor cannot
be
compared
with a ported and tuned twin rotor giving the same max. power output.
For example the acceleration time from 40-60 MPH in fifth gear is only
6.5
seconds as
compared to the standard time of 10.5 seconds = 40% faster, and a 0-60
in
a
little
over 5 seconds while still returning 25 MPG+ motorway driving, and an
added
bonus of
the triple rotor is the truly magnificent exhaust note. The engine has
excellent low
speed torque which makes it very easy town driving."
"The total weight of the Triple Engine is 315 lbs. together with
carburettor
and
exhaust system, is in fact 15 lbs. lighter that the standard RX-7
engine,
with
carburettor and exhaust system and is only 4 3/4" (120mm) longer."
"...for the ultimate in performance
600 BHP Hurley Quad Rotor Engine P.O.A.
900 BHP Hurley Six Rotor Engine Seeing is Believing ! "
Will it cool?
Will that tiny e-shaft diameter at the back end live under high
continuous
power?
Will the shaft couplings live?
What do the oil drain backs look like on the other side of the
intermediate
housings?
Paul Lamar
Paul,
Looks nice!.... E-Shaft strength and the harmonics going past four
rotors
seems to be difficult unless all things were design from the beginning
for
that use. I believe in bigger displacement after four rotor
configurations.
Very nice looking work on the engine.
Eric Barger
Paul,This thread seems to be mixing two different companies. Pulse is
in Nz and Hurley is in Uk,
In the facebook link above down in the comments there is a
response from Pulse concerning the E-shaft. As I read it they have bored
the shaft out of the e-shaft and splined the bores to correspond to
splines on the shaft and located these parts with "tappers" which may
mean
set screws. The counterweights are keyed. As described there are no
shaft
couplings. As for strength , the shaft is a larger diameter than a
transmission input shaft which on a race car can deal with 24 hour races
at 900 HP. I haven't found anything on the oil drain back but it is
workable
even if the OD of the stationary gear is used as a pilot by drilling
between the mounting holes for the oil to enter the intermediate
housings.
There likely would be some shaft wind up but each rotor is timed with a
stationary gear independent of the other rotors. In my opinion cooling
is
hopeless in a steady state condition. There have been housings converted
to
parallel cooling but I see no indication of this modification in either
of
these engines. Also a stock Mazda water pump would not circulate enough
coolant for parallel cooling beyond 3 rotors. The video shows a running
engine which is unloaded so it is only making enough power to turn it's
own parts, probably 30 HP.
As you might recall I was intending to do a six rotor. The plan
is
viable in all respects.It would be a standard 3 rotor accessory end
coupled
to a second 3 rotor on the drive end which has the removable eccentric
modified for a full diameter shaft. The end housings are dowel
aligned mating bell housings. The housing patterns incorporate all the
oiling/cooling and structural modifications and the waterpump (chrysler
hemi) and dry sump pumps are Nascar belt drive. I have altered the plan
back to 4 rotors due to airframe refinement in X-plane simulations. A
four rotor allows the use of stock RX-8 internals and rotor housings
which
are 1/3 the price of 3 rotor parts. Reducing engine weight and fuel
weight
significantly reduce landing speeds.
george grimes
If the shaft is not one piece there are couplings :)
Yes I know. I did it on purpose. The e-shaft couplings appear to be
different.
Here is the way CW did it on a four rotor. Makes more sense in many
regards (cooling,
tension bolts to name a few) but would require split intermediate
housing.
If you are
making billet housing that would be no real problem anyway.
The shaft may not break but one must deal with the flywheel coupling.
Paul Lamar
Paul, it would be great if you showed the photos or the innovative
REMOVABLE intermediate bearings Curtis-Wright came up with.
Bill Jepson
Here they are.
Paul Lamar
Thanks Paul,
One thing I really like about the CW bearing idea is that there is no real
need for a larger intermediate housing. In an Multi-rotor engine you could
shorten the engine considerably.
Bill Jepson
Bill, The wider intermediate housing is due to having intake and exhaust
ports in the housing not the bearing design. There are older housings that
can have both peripheral intake and exhaust ports at the expense of
efficiency and emission of Nox, however you still need a stationary gear.
The vertically split 2 piece style intermediate housing allows the
stationary gear/main bearing to be bolted to one face and the second face
added to complete the housing. This approach doesn't require a 2 or 3 piece
stationary gear and keeping the gear teeth aligned at 7500 RPM. Not
impossible to manufacture with todays machine tools but the parts also have
to be in a tapered bore to establish the bearing shell crush to make them
round and tight in the bore. Intuition tells me that steel gears and an
aluminum housing will change these clearances when up to operating
temperature from thermal expansion. As Paul mentioned there are stationary
bolt issues with added rotors. Going to .500 diameter is a plus and using
all the available bolt locations of the rotor housing rather than leaving
out two bolts as on recent versions would help. The other tension bolt
issue is they divide up the available real estate to the point that
parallel cooling particularly with RX-8 side exhaust is tough to do with
the standard width intermediate housing.
There seems to be a theory that CNC machined billet parts are a
cure all. To make a billet you must have an alloy that can be extruded in
an extrusion press. I was plant engineer for an Easco aluminum plant in the
1970's and 6061, 6063, 2024 and rarely a 75 something or other alloy were
pretty much all we processed. If you want the elevated temperature
properties and wear surface of the silicon carbide alloys like 398
aluminum you will be starting with a casting
Personally l would consider a shaft that was continuous from one end
to the other to be a one piece shaft.The Lemans 4 rotor had a continuous
shaft with the outboard eccentrics slid onto a tapered fit similar to the
rear counterweight on todays engines. I would concede that this
constitutes a 3 piece eccentric shaft. When I hear couplings that just
sounds like pieces of shaft segments joined end to end.
george grimes
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