Development of a shock noise prediction code for high-speed helicopters - The subsonically moving shockA previously defined airfoil subsonic shock-noise prediction formula whose result depends on a mapping of the time-dependent shock surface to a time-independent computational domain is presently coded and incorporated in the NASA-Langley rotor-noise prediction code, WOPWOP. The structure and algorithms used in the shock-noise prediction code are presented; special care has been taken to reduce computation time while maintaining accuracy. Numerical examples of shock-noise prediction are presented for hover and forward flight. It is confirmed that shock noise is an important component of the quadrupole source.
Document ID
19920031760
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Tadghighi, H. (McDonnell-Douglas Helicopter Co. Mesa, AZ, United States)
Holz, R. (McDonnell Douglas Helicopter Co. Mesa, AZ, United States)
Farassat, F. (McDonnell-Douglas Helicopter Co. Mesa, AZ, United States)
Lee, Yung-Jang (NASA Langley Research Center Hampton, VA, United States)