Experimental and analytical analysis of aerodynamic lift of an ornithopter at low and high angles of attack

Abstract

In this study, a model based on potential flow theory is developed to analyze the unsteady nonlinear aerodynamics of a flexible flapping wing at low and high angles of attack. It is assumed that the wing motion is composed of twisting and flapping. The developed unsteady two-dimensional model is applied to the flapping wing using a blade-element-type method. The computational model presented in this study shows better agreement with experimental data especially at a high angle of attack. Analytical results also show that the wings section does not necessarily twist linearly along the wingspan.

Keywords

Ornithopter flapping wing high angle of attack potential flow theory

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