Hi Paul:

Boy, you are opening a can of worms asking about chatter! In my opinion,
chatter is a phenomenon that has never been fully understood by anyone in the
rotary engine business even after spending mega bucks and years on research.
I have heard numerous theories. As I recall, the chatter frequency is too
high for it to be simply vibration of the seal / spring system. One theory
holds that it is the "ringing" of the rotor housing that causes chatter!
Lubrication definitely plays a role, as does seal mass. Curtiss Wright did
drill holes in the seals to reduce mass, and IIRC, that did change the
chatter situation. I think that most rotary developers converged on solutions
by a combination of analysis and testing that worked for their particular
engine and application without fully understanding why. My gut feeling is
that the Mazda system (seals, springs, materials, clearances, masses, surface
finishes, lubrication rate, lubrication introduction method...) works pretty
well as a result of both analytical and experimental approaches. That is not
to say that for non-automotive applications a modified system might not work
better. I think it will be hard for you to determine with limited testing
(one or two engines, a few hundred hours) if you are making an improvement or
possibly detracting from performance.

I'm not trying to dissuade you from trying new things, I just think that
understanding the results may be challenging.

Jon

I thought perhaps the three springs had some thing to do with it.
I am definitely going back to just two springs :-)

Paul Lamar
 
The Aircraft Rotary Engine Newsletter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org