Aerodynamic noise radiated from bodies in subsonic flow is caused by the generation, acceleration and interaction of vortices. Therefore, in order to reduce the aerodynamic noise, we need skillful turbulence management or control. In other words, it is most important to alleviate such vertical motions.In this paper, we examine noise reducing effects of pile-fabrics, namely cloth materials with fine and high density fibers like fur or down, that are used to cover the body surface. Simple tests show that pile-fabrics are very useful for reducing the vortex shedding noise, the turbulent boundary layer noise and the vortex interaction noise.

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