Abstract
This paper describes a simulation on the effect of the surface impedance for reducing aerodynamic sound from a circular cylinder. First, derivation of the ideal surface impedance that eliminates the pressure fluctuation on the body surface, is discussed. Then the simulation is conducted with using the Large Eddy Simulation (LES) techniques under the subject of Computational Fluid Dynamics (CFD) at Reynolds number, 3000. The imaginary domain under the surface is introduced to realized the effect of the finite impedance. In the simulation only larger impedance than the ideal one is applied to the surface due to the computational instability which restrains the lower limit of impedance. Even for the larger impedance, effect, of setting-up the surface impedance is verified by the simulation with the fact that the amplitude of the surface pressure fluctuation decreases remarkably.
