On the kinematic parameters, airfoil thickness and unsteady mechanisms and their effects on the aerodynamics of a flapping airfoil in hovering flight at low Reynolds numbers

  • M.T. Kashani
  • S.M. Hashemi
  • F. Talebi

Abstract

The influences of different flapping patterns, amplitude of oscillation, airfoil thickness and
two unsteady lift-enhancement mechanisms, namely, wake capture and delayed stall on the aero-
dynamic performance, instantaneous and timeaveraged aerodynamic force coefficients, and flow patterns of an elliptic airfoil, performing flapping motion, at low Reynolds numbers (Re) are investigated by means of computational fluid dynamics. For this purpose, a numerical simulation of 2-D time dependent Navier-Stokes equations discretized based on finite volume method, is performed. All the pattern are dynamically scaled at Re=75 to facilitate the comparison. The simulation results reveal that the flapping pattern, amplitude of oscillation, wake capture and delayed stall mechanisms affect the maximum and time averaged lift and drag coefficients and aerodynamic performance of the flapping motion while the influence of airfoil thickness in the range of 2% to 12% on these parameters is negligible.

Published
2013-11-24
Section
Articles