Aerodynamic admittance functions of streamlined bodies: the indicial approach by CWE

This paper proposes a method to determine the aerodynamic admittance function of 2-dimensional cylinders by means of a modified indicial approach adapted to a Navier-Stokes solver. The method is based on the simulation of a smoothed-edge gust passing the cylinder and on the evaluation of the transient forces arising on the obstacle. An application to a thin plate is proposed. Firstly, the numerical parameters of the model are optimised by simulating two elementary flow conditions: the gust propagation in a free stream and the steady flow around the plate. Then, both the gust and the plate are introduced in the same computational model. The computed aerodynamic admittance function is compared with the one provided in closed form by Sears in the frame of the thin airfoil theory