The small-disturbance potential equation appropriate to a helicopter in forward flight is derived. This equation is then solved for the flow over a nonlifting transonic rotor blade, using a completely implicit scheme that is an extension of the Murman-Cole mixed-difference technique. The flow in the tip region is most unsteady in the decelerating flow region, after the blade passes the psi = 90 deg azimuthal station. The unsteadiness appears to be caused by expansion and compression waves that move slowly upstream of the blade as the relative incident flow decelerates. The influence of aspect ratio, advance ratio, and Mach number on this process is discussed.
Numerical calculation of unsteady transonic potential flow over helicopter rotor blades
American Institute of Aeronautics and Astronautics, Aerospace Sciences Meeting ; 1975 ; Pasadena, CA
1975-01-01
Conference paper
No indication
English
Unsteady Transonic flow over Helicopter Rotor Blades: Non-Lifting Potential Calculations
British Library Conference Proceedings | 1993
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