Numerical and experimental investigation of pitching / plunging airfoils in hover

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2012
Hızlı, Hasan
In this thesis, results of the numerical and experimental study corresponding to four airfoils, namely SD7003, NACA0012, 10% thick elliptical, 10% thick flat plate, undergoing sinusoidal pure pitch, pure plunge and combined pitch-plunge types of hovering motion are presented. A number of cases are investigated consisting of different pitching and plunging amplitudes. The study aims to provide a better understanding of the aerodynamics phenomena and the vortex topology of flapping wings in motion for application to micro air vehicle (MAV) designs, to investigate the effect of pitching and plunging amplitudes on the different modes of hovering motion and to compare the numerical and experimental results for validation of the newly built experimental setup with the numerical simulations by means of the instantaneous flow topologies. The unsteady, incompressible Navier-Stokes equations are solved for the extensive numerical simulation of the flow field around the airfoils whereas the instantaneous velocity field data of the flow are acquired by the Particle Image Velocimetry (PIV) measurements. An agreement between the numerical and experimental results of the investigated test cases is observed in terms of the instantaneous vortex structure of the flow. Among the studied cases, the highest mean lift coefficient is obtained from pitching-plunging (αa=30o, xa=0.01 m) SD7003 airfoil while the lowest is obtained from purely plunging (xa=0.02 m) 10% thick flat plate airfoil. Moreover, pitching-plunging (αa=30o, xa=0.02 m) SD7003 airfoil gives the lowest mean drag coefficient whereas pitching-plunging (αa=45o, xa=0.01 m) 10% thick elliptical airfoil gives the highest.

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Citation Formats
H. Hızlı, “Numerical and experimental investigation of pitching / plunging airfoils in hover,” M.S. - Master of Science, Middle East Technical University, 2012.