Hi Paul,

Thanks for your book. I am learning a lot. I also noticed
a nice Wiki on the subject; at:

 http://en.wikipedia.org/wiki/Wankel_engine#How_it_works

Any comments?

Dave Silverberg
Aestiva

Aestiva
Phone: 1-888-237-8482
Phone: 1-310-697-0338
Email: dms@aestiva.com


It is pretty good only a few mistakes :)

Paul


Hi Paul,

I have been reading your book...it really makes me think.

Here's an off-the-wall question:

I was doing a bit of thinking about the re-sizing of a rotory engine.
I have had a bit of difficulty since I am not used to thinking much. But
here it goes...

 (Note: R3 means R-cubed, R2 means R-squared)

 Since the combustion cavity (Amount of fuel one can burn) is liner with
 volume (R3) and the size of surface area (for heat exchange) is linear
 with area, then a 50% reduction in cavity volume (and HP) corresponds
 to only a 25% reduction in cavity surface area -- thus allowing for
 twice the effective heat exchange per HP. So smaller the engine, the
 easier the heat exchange.

 Is this true? I am assuming the same temperatures are reached by the
 ignited fuel?? Is it also true that, the material weight needed for a
 smaller engine goes down by volume (R3) or not?

 I ask because I wonder whether small rotary engines are appropopriate
 to power a very small remote control helicopters? One that could lift
 up to five or ten pounds? Would it not beat out other devices? On the
 other hand, perhaps electric engines are better???

- Dave


BTW, I saw on the web a hobbyist that specializes in building, from
scratch, working engines of this size.

I hope I am not bothering you.. it is fun to think about these things.
Kind of reminds me of 1984 - when you sold me the Stride.

- Dave

Yes it is easier to cool but the downside is more heat loss to the
coolant which translates to less HP per pound of fuel burned. This explains the
popularity of large four cylinder engines over smoother six cylinder
engines both with the same overall displacement. This is the approach
Mazda is taking with the new 16X. A 3.2 liter two rotor as opposed to
their existing 3.9 liter three rotor 26B and the current 2.6 liter
RX8 engine.

Paul Lamar ...No rotor no motor.

The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
Copyright 1998-2007 All world wide rights reserved.