Viscous/inviscid interaction procedure for high-amplitude oscillating airfoilsA coupling procedure between an inviscid potential theoretical panel method and an unsteady interactive boundary layer calculation procedure has been developed for calculating unsteady airloads on oscillating airfoils in the high-incidence regime. A coordinate transformation into a time-dependent surface coordinate has been incorporated into the boundary layer code to avoid a quasi-steady treatment of the viscous flow equations in the leading edge region. The upper and lower sides of the airfoil are calculated with the complete set of unsteady equations. The interactive region of the boundary layer calculation can be straightforwardly extended over the complete upper surface of the airfoil while accounting for interaction areas in the region of strong adverse pressure gradients with incipient separation. Comparisons of sample calculations with experimental data show reasonably good agreement even for unsteady drag coefficients.
Document ID
19890026208
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Geissler, W. (DFVLR, Institut fuer Aeroelastik, Goettingen Federal Republic of Germany, United States)
Carr, L. W. (NASA Ames Research Center; U.S. Army, Aeromechanics Laboratory, Moffett Field CA, United States)
Cebeci, T. (California State University Long Beach, United States)