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Numerical Simulation of Flapping Airfoil Aerodynamics Using a Lagrangian Particle Based Technique

S. Sarkar

Abstract


A Lagrangian viscous vortex technique is used in the present study to simulate the unsteady flow field of flapping flight. The method is grid free and computations are done only at the regions of non-zero vorticity. As a result this method is quite suitable for simulating the unsteady vortical flowfield past flapping wings and airfoils; it is faster than grid based solvers and provides quick flow visualization. Heave and pitch kinematics are fundamental to any flapping type MAVs. A set of pure sinusoidal plunging and its kinematically equivalent pitching using the same reduced frequency are investigated. The focus lies in investigating the advantage of the Lagrangian method over grid based CFD solvers in capturing the flow field. Experimental observations have been taken as benchmark for different cases considered. Effect of mean angle, starting conditions, nondimensional stroke amplitudes are considered. In the subsequent part, sinusoidal hovering of a symmetric airfoil at moderate Reynolds number is studied. The unsteady load generation mechanism during hover is looked into.

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References


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DOI: http://dx.doi.org/10.21535%2FProICIUS.2010.v6.478

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