An Application of the Blade Element Theory to Estimate Unsteady Aerodynamic Force Produced by a Flapping Wing

Abstract

In this paper, we present an application of the blade element theory (BET) model to estimate the aerodynamic force produced by a freely flying beetle. In the BET model, we consider translational force, added mass force, and inertial force. The lift and drag coefficients are used from the measured data for a dynamically scaled model of Drosophila wing in a reference paper. The aerodynamic forces of the model are estimated and compared with the measured data. The results computed by the BET model show a good agreement with the measured ones. After the validation, the BET is used to calculate the lift and thrust forces produced by a freely flying beetle, which flaps its wings at a relatively higher Reynolds number compared to that of the dynamically scaled model of Drosophila. To confirm the computed results, a freely flying beetle was filmed and analyzed to estimate the acceleration of the beetle. The results show that the BET can be a good tool to estimate the forces produced by a flapping wing motion, which is an important step to design and study the stability of a manmade flapping-wing micro air vehicle.