An entropy and viscosity corrected potential method for rotor performance predictionAn unsteady Full-Potential Rotor code (FPR) has been enhanced with modifications directed at improving its drag prediction capability. The shock generated entropy has been included to provide solutions comparable to the Euler equations. A weakly interacted integral boundary layer has also been coupled to FPR in order to estimate skin-friction drag. Pressure distributions, shock positions, and drag comparisons are made with various data sets derived from two-dimensional airfoil, hovering, and advancing high speed rotor tests. In all these comparisons, the effect of the nonisentropic modification improves (i.e., weakens) the shock strength and wave drag. In addition, the boundary layer method yields reasonable estimates of skin-friction drag. Airfoil drag and hover torque data comparisons are excellent, as are predicted shock strength and positions for a high speed advancing rotor.
Document ID
19890031486
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Bridgeman, John O. (Woodside Summit Group, Inc. Mountain View, CA, United States)
Strawn, Roger C. (NASA Ames Research Center Moffett Field, CA, United States)
Caradonna, Francis X. (NASA Ames Research Center; U.S. Army, Aeroflightdynamics Directorate, Moffett Field CA, United States)