Experimental and numerical investigation of flow field around flapping airfoils making figure-of-eight in hover

Başkan, Özge
The aim of this study is to investigate the flow field around a flapping airfoil making figure-of-eight motion in hover and to compare these results with those of linear flapping motion. Aerodynamic characteristics of these two-dimensional flapping motions are analyzed in incompressible, laminar flow at very low Reynolds numbers regime using both the numerical (Computational Fluid Dynamics, CFD) and the experimental (Particle Image Velocimetry, PIV) tools. Numerical analyses are performed to investigate the effect of different parameters such as the amplitude of motion in y-direction, angle of attack, Reynolds number and camber on the aerodynamic force coefficients and vortex formation mechanisms. Both symmetric and cambered airfoil sections are investigated at three different starting angles of attack for five different amplitudes of motion in y-direction including linear flapping motion. Experimental simulations are performed in order to verify the numerical results only for linear motion at Reynolds number of 1000 for symmetric and cambered airfoils at three different angles of attack. Computed vortical structures are then compared to vorticity contours obtained from the experiments and advantages of figure-of– eight motion over linear motion are discussed.


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Citation Formats
Ö. Başkan, “Experimental and numerical investigation of flow field around flapping airfoils making figure-of-eight in hover,” M.S. - Master of Science, Middle East Technical University, 2009.