Subject: Combination slide throttle and carburator (Atomization)
From: Rotary Engine
Date: 11/13/2006, 10:07 PM
To: AA-me



   Paul,
   While I like the simplicity of the idea, and believe with the right
   ramp profile it CAN work, dribble systems are never going to be as
   efficient as FI. Fuel atomization is the first reason. By its very
   nature this system can't be high pressure, it is a fixed pressure
   variable orifice system. It would have to be over rich in most of the
   mid range to be operable. Many things will run, most not very well. I
   saw a photo of a guy that got himself out of the desert of Baha after
   rolling his bug and smashing the carb. He ran the hose from the fuel
   pump into the point end of a BIC pen he pulled the guts out of. Duct
   tapped the thing over the inlet bell and it ran shoving gas out through
   the little hole on the side of the pen! He even told the press guys that
   it worked pretty well at "bout 50". Mechanical fuel pump made it a kind
   of ultra-primitive FI. The flat slide idea could be ok but never as
   precise as good FI. Perhaps as a redundant system would be its best use.

   By the way I checked and Lectron is still in business. They have some
   very sophisticated ground needle systems. They could be incorporated in
   the center of the slide throttle to improve mixture control but then
   your simplicity goes out the window. You're making a carb again. BTW the
   system WOULD be subject to icing. Though typical carb heat could be used
   with it.
   Bill Jepson

   It is not like this is a new idea. Klaus flies an Ellison
   on his O-200 and gets 50 MPH at 200 MPH. What is inefficient
   about that? Gravity feed no less. All the pumps do is fill
   the header tank. I know half a dozen people running these
   types of carbs and they are getting better MPG than we are
   with EFI.

   http://www.aeroconversions.com/carb_saying.html
   http://www.ellison-fluid-systems.com/article/notaposa/notaposa.htm
   http://revmasteraviation.com/products/revflow_injector_carburetor/index.htm

   These are becoming universal on cert engines in experimental
   airplanes because they are simple and relatively cheap.

   If you have some data or documentation to support
   your inefficient or atomization claims I liked to see it.

   EFI is not worth the high cost and the redundant electrical
   system required to make it safe.

   Paul Lamar ...No rotor no motor.

   Paul,

   I think your original idea with the many small holes would work better
   for atomization. That's the idea behind the Ellison fuel spray bar which
   uses lots of tiny holes to achieve very fine atomization.

   Regards,

   Gordon.


   Paul,

   Actually, looking at your drawing it's not really analogous to how
   the Ellison works.

   You could make it work like the Ellison by having a series of very
   fine holes in the aluminum plate where you now have your fuel
   delivery hole. So that when your Teflon plate slides across those
   holes, it opens up more fuel spray holes as the throttle is opened,
   and blocks them as the throttle is closed.

   You would have to have an oval hole in the top of the Teflon part
   that would open to the tiny fuel spray holes so they could have a
   straight shot.

   Regards,

   Gordon.

Well one thing is the Ellison has holes in one side of
the needle only. The needle rotates to change the mixture.

To make my original system more like the Ellison all the holes
in the Teflon would have to be very small and be the same size.
A slot in the spacer would open more and more holes to the fuel
port as the the slide throttle was opened. I'll do a 3D soon.

I'll be at Mazdatrix tomorrow working on Marks P-port
engine until about 4 PM.

Paul Lamar ...No rotor no motor.

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