"Quirk, Kevin KA" wrote:

 Does anyone have any ideas on the following question?  I send it out previously but haven't had any responses.

What usually limits the RPM on a 13B engine?
e.g. airflow, rotor bearing load, stationary gear failure, lubrication problems, apex seal dynamics?


KQ

EOM

In an airplane it is the prop. A practical fixed pitch prop with a 2.17:1  PSRU is 
limited to about 6300 RPM wide open throttle.

In a car with a gear box the RPM is limited by the rotor bearing loads
right at the moment. At one time it was the phasing gears but they have been
improved.
The loads on the rotor bearing limit the engine to about 10,000 RPM.

The new rotor for the side exhaust port engine are reported to be 
14% lighter in weight and the load on the bearing is m*V^2/r
m is is in slugs so you need to divide the rotor weight in pounds by 32 
to get slugs. r is the radius of the eccentric and V is the tangential velocity
of the CG of the rotor in feet per second. 


Current rotors weigh
about 8.5 to 9 pounds.

This is probably more than you wanted to know :-)

Paul Lamar

 
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