Aeroacoustic simulation of bluff body noise using a hybrid statistical method

Abstract

The prediction of aerodynamic noise generated by bluff bodies is important for a broad range of technologies, such as aircraft landing gear and automotive external mirrors. However, accurate prediction is difficult and time-consuming due to the complicated flow physics that occurs in the near wake. Typically, noise predictions require computationally demanding three-dimensional flow simulations that are usually not practical for engineering use. In this paper, a method is described where two-dimensional flow simulations are used with a statistical model to introduce the effects of flow three-dimsionality into the acoustic source calculation procedure. The result is a noise prediction method that is many times faster than conventional methods. The paper will describe the method, its advantages and disadvantages and use it to simulate the noise (Aeolian tone) from a cylinder placed in a flow where its wake is turbulent (and three-dimensional). The method is shown to accurately capture the spectral broadening about the main tone.