The characteristics of the Aeolian tone radiated from two-dimensional cylinders

Abstract

Aerodynamic sound radiated from cylindrical objects, such as in a pantograph of a train, is a prime noise source in high-speed vehicles. The objective of this paper is to understand the generation mechanism of aerodynamic sound radiated from two-dimensional cylinders. Basic theories for aeroacoustics are reviewed. Three contributions to the field of experimental investigations of the Aeolian tone generation mechanism by the present author are reviewed. The structure of the low-noise wind tunnel and the use of proper model end plate construction to control acoustical and flow fields are discussed in section 3. Experimental investigation on the characteristics of aerodynamic sound radiated from two-dimensional models, such as a circular cylinder, square cylinders with or without rounded corners and a cylinder with modified square cross-section, is discussed in section 4. Experimental investigation of Aeolian tone generation and its relation with surface pressure fluctuation on a circular cylinder at moderate to high Reynolds number flow are discussed in section 5.