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



    Hi Paul, Further to my thoughts on CC turbulence. It is well known
    (as you know) that recip engines rely heavily on this effect. In
    two valve per cylinder  it relies on "swirl" as the mix comes in
    through one valve and out the other. This spin effect is increased
    as the piston comes up, rather like an ice skater as they move
    their arms in to greatly increase their spin. In an engine with two
    valves per cylinder it "tumbles" instead rather like an acrobat or
    diver doing a forward roll. Possibly the turbulence could also be
    improved by injecting hot air in through the trailing plug hole
    (NOS would be better !) this will give a small (or even big)
    supercharging effect also. Of course this will affect the mixture
    and must be allowed for. Chris. p.s. no need to put this in if you
    think it's all bullshit.


    There is a very Fundamental difference in the moving combustion
    chamber of a Wankel and the fixed combustion chamber of a piston
    engine. Apples and oranges.

    Paul Lamar


    The trailing plug would be too late in the intake for the cooling
    effect of the NOS injection to provide a "supercharging" effect.
    Injecting about 45°after the intake opening in combination with
    direct fuel injection as illustrated in photos from Mazda of the
    16X rotor housing. Also incorporation of the Far Trailing plug as
    used in the Le Mans winning engine would help with BSFC and
    emissions. NOS is only good for short power bursts.

    My feeling regarding hydrogen as a fuel is that it is a future
    possibility. In the interim, a focus on the use of natural gas
    would be more beneficial. It burns clean and can be used in
    modified diesel engines. In a rotary engine, fairly high boost
    pressure could be used on engines like the 10A and 13A with 3 spark
    plugs. Using Paul's ignition system for very complete combustion
    would provide high power and low emissions. Natural gas is
    inexpensive and fueling can be done at home overnight or at quick
    fill stations. Fuel costs for a year of driving should be less than
    gasoline providing driving conditions and miles driven remain the
    same.

    Dale Davies


    What does all that have to do with the squish flow?

    Paul Lamar



    Hi Paul, When I re-read my missive on turbulence I noticed my
    second instance involving " tumble " was meant to read four valves
    per cylinder not two.

    Cheers Chris Hoskins


    On recip engines in the early emissions days lower compression
    ratios were desired thus the Big Three made use of open chamber
    heads. These had larger combustion chamber volumes and tapered to
    the cylinder walls. Newer research has found the quench heads
    better. Ford and the others developed heart shaped combustion
    chambers that enhance combustion efficiency.

    As Barry explained swirl from a two valve head speeds the spread of
    the flame front.I believe the air/fuel squished out between the
    quench part of the head and the rising piston also promotes tumble.
    Too much can be detrimental. In four valve heads tumble is more
    prevalent. The Detroit Diesel two strokes had the inlet ports at an
    angle to initiate swirl. Even though the rotary combustion chamber
    works differently, I believe combustion theory applies as Laws of
    Physics. It is just a matter of determining what works best. I
    believe Barry's findings corroborate what the other auto
    manufacturers are finding.


    Somender Singh got a patent for "groove" technology that helps with
    swirl and possivly tumble. If grooves were machined into the
    trailing side of the rotor face to direct a blast of air/fuel
    forward past the spark plugs to carry the flame to the front edge
    and then back down the sides may help fuel burn. Using the far
    trailing plug would also help if possible to incorporate. The third
    plug would tend to send a jet of rapidly expanding flame along the
    groove.

    Dale Davies

    None of the first two paragraphs  is applicable to the rotary.
    Apples and oranges.

    Do you have any drawings or the patent itself? Or just the patent
    number?

    Paul Lamar


    How about putting tapered reversing swirl ports in the depression to
    swirl and reverse flow. They could also act as a catch to for the
    flame front to thrust against the rotor. It would have to be a
    catalyst surface to be self cleaning. I'm just thinking, there maybe
    be a 1000 reasons why this wouldn't work but I can't think of any.

    Kurt Emerson

   No amount of swirl, turbulence, tumbling etc. etc. is going
   to help if the fire is not in the right e-shaft angle region.
   It is all just blown away.  The air speed in the combustion
   chamber at this point is 90 meters per SECOND! That
   is 270 feet per second or 184 MPH!!! Here is a chart for
   two different combustion chamber shapes. The wind
   direction changes. This is from Rotary Engine.

   Wind in the world is created by an atmospheric difference in pressure.
   The larger the pressure difference the stronger the wind. That is how they
   predict weather changes  in general.

   The same thing happens in the Wankel combustion chamber. A large difference
   in pressure is created IN THE COMBUSTION CHAMBER when
   the back side of the rotor rapidly approaches the rotor housing.
   The front side is rapidly moving away lowering the relative pressure.
   That will force the fire away from the optimum e-shaft angle.
   This is entirely different from what happens in a piston engine.
   There is no reason for the fire to move relative to the spark plugs.

   I suspect several surface gap plugs would help north of the upper plug
   as would redirecting the wind flow.

   Paul Lamar

Web site: somender singh.com <http://singh.com>.  The USpatent is #6237579 issued May 2001.
Barry stated he has found low or no burn at the combustion chamber sides along where the side seals are. This coinsides with Mazda's own research that found rotor widths over 75mm had incomplete combustion.


You mention the optimum eshaft angle for the combustion pressure. What would that be? 90° to the eshaft top dead center?
You also state that it would be beneficial to reverse the gas flow toward the trailing end of the rotor face. Is that to get the pressure there or the flamefront? Mazda found an improvement in BSFC and torque with the use of the far trailing spark plug on the Le Mans winning engine.


Would that be from the more complete fuel burn or increased pressure on the trailing end of the rotor face? I believe it increases the burn which increases the combustion pressure. The rotor motion pushes that hot burning gas toward the rotor leading end. With use of the third plug and a y groove cut with a short groove along the center of the rotor to pick up the ignited fuel mixture as it passes. The top ends of the y could be pointed forward and to the sides to help get that burning along the sides.


The rotary engine, reciprocating engine and turbine engine are all very different. Gas flows work differently. The one thing that remains consistant is that turbulance aids combustion efficiency. I do not think turbulance is a problem in turbine engines.
Dale Davies


I think the combustion pressure peak is delayed beyond the optimum angle.

An improvement could be as simple as a .1 inch depression in the face
of the rotor near the trailing apex seal. The floor of the bath tub can
be raised to keep the compression ratio the same. That would reduce
the pressure difference and reduce the squish wind velocity.

Paul Lamar

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