Within the Sonderforschungsbereich 25 the development of the leading-edge vortex system and its influence on the unsteady aerodynamic forces were investigated experimentally and numerically. Two different flow configurations were considered: an airfoil at a fixed high angle of attack in unsteady flow and an oscillating airfoil in steady flow. The experimental study was performed using a Water-Ludwieg-Tunnel. The velocity fields were visualized by particle path methods, while the aerodynamic forces were measured by a three-component strain gauge balance. Numerical investigations are performed by finite-volume method, based on the Navier-Stokes equations for incompressible flow. In both cases processes were observed similar to dynamic stall: The triple vortex structure, which consists of the primary, secondary, and tertiary vortex were formed. The secondary vortex cuts the connection between the primary and the tertiary vortex and completes the dynamic stall. The agreement between experimental and numerical results for the flow field and the aerodynamic coefficients is good.
Formation and structure of vortex systems around a translating and oscillating airfoil
Bildung und Aufbau von Wirbelsystemen um einen sich fortbewegenden und schwingenden Tragflügel
Zeitschrift für Flugwissenschaften und Weltraumforschung ; 19 , 6 ; 391-396
1995
6 Seiten, 12 Bilder, 9 Quellen
Article (Journal)
English
Tragflügelumströmung , Wirbelströmung , Aerodynamik , Strömungsvorgang , NACA-Profil , Anstellwinkel (Tragflügel) , instationäre Strömung , Schwingungsverhalten , stationäre Strömung , Wasserkanal , Geschwindigkeitsverteilung , sichtbare Strömung , Kraftmessung , Dehnungsmessstreifen , Navier-Stokes-Gleichung , inkompressible Strömung , Abreißen der Strömung , Strömungsgeschwindigkeit , Argonlaser , Kamera , Flügeloberseite , Stromlinie , Beschleunigung , Rechenmodell , reibungsbehaftete Strömung
Formation and structure of vortex systems around a translating and oscillating airfoil.
Online Contents | 1995
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