Accession Number : ADP001950

Title :   Theoretical and Experimental Dynamic Stall Investigations on a Rotor Blade Tip,

Corporate Author : DEUTSCHE FORSCHUNGS- UND VERSUCHSANSTALT FUER LUFT- UND RAUMFAHRT E V FREIBURG IM BREISGAU (GERMANY F R)

Personal Author(s) : Geissler,W.

Report Date : 1982

Pagination or Media Count : 6

Abstract : Theoretical and experimental investigations have been carried out on oscillating blade tips at moderate and high steady mean incidences and oscillation amplitudes. Some selected data of these tests are compared with a previously developed prediction method based on potential theory to investigate the main effects of viscosity in different domains of dynamic stall. A simple correction procedure is described to take into account the main effects of viscosity on the unsteady airloads. To get a more detailed insight into the beginning of unsteady separation on oscillating profiles a finite-difference procedure has been developed to calculate the unsteady boundary-layer equations. This method has been applied to the oscillating flat plate problem as a first step. The applications to problems of more practical interest like profiles under pitching motion is straightforward. (Author)

Descriptors :   *Rotor blades(Rotary wings), *Stalling, Helicopter rotors, Oscillation, Viscous flow, Flat plate models, Vortices, Wake, Finite difference theory, Wind tunnel models, Wind tunnel tests

Distribution Statement : APPROVED FOR PUBLIC RELEASE