BTW can anybody tell me why my
   air passages in this rotor housing
     are a bad idea? This is a quiz.

     Paul Lamar


     They
 allow high pressure
   combustion gases to
 pass back to the intake
      side. This
 would cause
   preignition. BIG no no!

     Dale Davies

     Possibly but there is
 one other
   problem.

     Paul Lamar

     Compression pressure bleedoff
   and out the exhaust. Low cylinder
     pressure and high exhaust
   emissions. Dale Davies

     Not exactly.

     What do you mean "out the
   exhaust." ?

     Paul Lamar


     It will blow the
 combustion
   cycle back into the previous
 chamber as
     apex passes inlet to
 bypass. And
   the timing would be static.
 The
     rotor design stays with the
   combustion

     Kurt Emerson

     Well yes but that is not what I
   had in mind. There is another factor
     in play here. Can anybody think
   what that is?

     Paul Lamar



   That the
 passage would cause that area
   to be even
 hotter than it already
   is, and its
 already a problem area.


 Dan Gorsline


   Not yet :-) That is not it.

   It is a well known problem
 you should
   know about.


   Paul
 Lamar


 Paul
 and all,
 We would be bleeding pressure from
 the 45deg ATDC big push on the rotor.

 But my problem is with the original premise...
 that we should divert the
 hurricane
 flow.
 And secondly that we should add
 surface area... both of which are a
 detriment to the Rotary.

 The spark kernel needs turbulence to develop
 quickly.  It is also helped
 by compression
 and temperature.
 Attached is a quote from
 Sir Harry Ricardo.

 On the
 GM patent I think if we could change the stainless by-pass

 inserts to non-bypass vacuum SS inserts
 (think thermos bottle) to
 minimize heat
 loss it would be a great help.

 Barry Bordes

 Why do you think surface area is a problem?
 There will be no combustion
 under
 a metal plate on top of the rotor. I am sure
 General Motors checked that
 before they
 applied for their patent. The area  is too
 thin at .1 inch to support
 combustion.

 A very important part of this
 idea is to relive the high pressure in
 the
 area where the aft part of the rotor is in close contact
 with the
 wall of the rotor housing. That
 will reduce the velocity of the wind storm.

 There is also not a reduction
 in pressure due to squish flow under the top
 plate on top of the rotor. There is a slight
 reduction in compression ratio
 but that
 could be made up  with a shallower bath tub.

 Turbulence is fine but a wind
 storm on top of the rotor blowing the
 mixture down stream
 is
 something else. That blows the combustion away from the
 optimum
 e-shaft angle.

 Yes I agree about a vacuum's ability to
 insulate but ceramic rotors have
 been
 built
 with no significant improvement in
 BSFC. I suspect  GM found that out
 when
 the
 tested the 2 piece rotor.

 It is called the adiabatic
 Wankel but it was a big disappointment.

 The flow in the combustion chamber is the only
 really significant difference
 between the
 Wankel and a piston engine.

 Paul
 Lamar

Paul,
Any cool area that cannot enter into the combustion process will lead to wasted energy.
An example would be the area above the side seals.

 I went the opposite way.
 I increased the turbulence and flow at the sparkplug and found a measurable difference.
The burn rate increased as shown with combustion testing.
It then required removing 2 degrees of timing. (see attached)

The best solution IMHO would be a way to seed the chamber with a catalyst-like substance
 that would simultaneously ignite over all of the rotor face captured area.
Barry Bordes

Yes but it is not enough to affect the BSFC by 10%. Something else is going on.
I think it is the wind in the combustion chamber.

Your catalyst might work.

You also need a way to test the BSFC.  If you have a prop on the engine and
you run it at a constant RPM long enough to burn a gallon of gas you
can test the BSFC by how long it takes to burn a gallon. The longer it runs
the better the BSFC of course.

It will be hard to measure the effect ( if any ) on that NACA duct.

Paul Lamar

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