Identification of aero acoustic noise sources using the inverse boundary element method

This paper explores the use of the inverse boundary element method to identify aeroacoustic noise sources. In the proposed approach, sound pressure at a few locations out of the flow field are measured, followed by the reconstruction of acoustic particle velocity on the surface where the noise is generated. Using this reconstructed acoustic particle velocity, the acoustic response anywhere in the field, including in the flow field, can be predicted. This paper will also show that only a relatively small number of sound pressure measurements are required for the inverse BEM and that these measurements need not be in the near field of the source nor conformai to it to obtain good results. Examples include an open-ended duct and a prediction of vortex shedding noise from a circular cylinder.