Accession Number : ADP005013

Title :   Unsteady Boundary-Layer Separation on Airfoils Performing Large-Amplitude Oscillations: Dynamic Stall,

Corporate Author : DEUTSCHE FORSCHUNGSANSTALT FUER LUFT- UND RAUMFAHRT EV GOETTINGEN (GERMANY F R) INST FUER AEROELASTIK

Personal Author(s) : Geissler, W.

Report Date : NOV 1985

Pagination or Media Count : 12

Abstract : Experimental investigations have exposed a strong dependency of unsteady separation characteristics in the regime of dynamic stall on airfoil shape, Reynolds and Mach number, frequency and time-dependent incidence. A suitable prediction method should therefore be able to account for these various parameters. Coupling procedures between two-dimensional unsteady boundary layers and inviscid surface singularly methods (panel methods) have been developed for analytical investigation of unsteady turbulent separation. In the present study, the influence of various parameters on unsteady separation is discussed in detail and comparison with experimental data is made. The results show that, even for weak coupling between boundary layer and inviscid boundary conditions, good correspondence exists between theory and experiment with respect to the development of unsteady separation.

Descriptors :   *FLOW SEPARATION, *STALLING, BOUNDARY LAYER, UNSTEADY FLOW, OSCILLATION, AMPLITUDE, AIRFOILS, TURBULENCE, COUPLING(INTERACTION), INVISCID FLOW, MATHEMATICAL PREDICTION, TWO DIMENSIONAL FLOW, WEST GERMANY.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE