Subject: Donkey Engine? (was 40% less fuel)
From: ACRE NL
Date: 10/5/2002, 3:27 AM


That is cool.  I'll bet a turboed 3 rotor could win Reno easily
running
in that configuration.

Chris
microcosman.com

YES - That is indeed "cool". Now that version is a true rotary, and
would
not require any
counterbalances. The tip seals would have a constant centrifugal
loading,
and rpm structural
loading limits would be pushed up. However the sealing and induction
system
must
be rather complex, and would be the probable limiting items. Also, there
is
no reason
to expect the power per envelope to be significantly different than the
current
configuration. - Vance J

Let me get this straight.

A two bladed prop is a "true" rotary prop but a one bladed prop
with counter weight is not a "true" rotary prop?

A World War I rotary radial piston engine is a "true" rotary engine with
oscillating connecting rods but a Mazda rotary with absolutely
nothing oscillating or reciprocating yet it has counter weights
is not a "true" rotary engine?

A two rotor Mazda rotary engine has counter weights
and is not a "true" rotary engine but a four rotor Mazda
engine requires no counter weights and is a "true"
rotary engine?

New World Dict... "rotary"... of, or having the nature of, rotation.

Last time I checked the formula for HP was (RPM X TORQUE)/5252.

All other things being equal why would I not have five times
the HP if I had five times the RPM with the same torque... read
displacement?

VJ - The housing was rotating at high speed, but pumping is determined
by the relative speed between the housing and the rotor, and the rotor
was turning in the same direction but slower, and the cyclic rate of the
power pulses was not automatically high, You make power by
pumping and expanding air, and the high rpm of a part of that device
 is not directly relate to lots of power. Actually with that
configuration you could take rower from the slower turning
rotor - same HP - more torque lower rpm - Vance

The whole point of the original wankel engine is the centrifugal force on
the rotor bearing is eliminated compared to the Mazda therefore there is no mechanical limits on
rotating speed to the point of the outer housing disintegrating from simple over stress. Right at
the moment the HP and
rotating speed of the current engine is limited by the centrifugal loads on 
the rotor bearing. That is why the cast iron (perhaps cast steel) RX8 engine 
rotors are lighter. Fabricated 4130 steel sheet rotors or titanium 
or aluminum rotors with steel wear inserts would be lighter still.
 
Pumping is the same as the Mazda. 

The big problem, as we both pointed out, is getting cooling fluids and
combustion  gasses into and out of the rotating outer housing without 
leaks. One of the same problems the WW I rotary radials had. You would 
still need a gear box to take advantage of the high power potential.

Paul Lamar
 
 
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