Fluid reaction surfaces (i.e. – impellers) – Specific blade structure – Flexible
Reexamination Certificate
2007-05-31
2010-12-28
Edgar, Richard (Department: 3745)
Fluid reaction surfaces (i.e., impellers)
Specific blade structure
Flexible
Reexamination Certificate
active
07857598
ABSTRACT:
The twist distribution of torsionally-flexible rotor blades is adjusted by exploiting centrifugal effect on inertial torquers affixed at one or more stations along the blade span. Twist is thereby made to vary passively as a function of rotor speed and hub incidence angle. With inertias of appropriate size and location, the twist variation is such that high rotor efficiency is maintained over a wide range of operating conditions. Satisfactory dynamic behavior of the blade, including cyclic-pitch response and flutter resistance, is simultaneously achieved.
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McGeer Brian T.
von Flotow Andreas H.
Aerovel Corporation
Edgar Richard
K&L Gates LLP
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