Direct Evaluation of Acoustic-Intensity Vector Field Around an Impedance Scattering Body

摘要

The paper presents a direct method for predicting the acoustic-intensity vector field around an impedance scattering body. The results obtained from the present method, combined with the equivalent-source method, graphically display the acoustic-intensity vector field around the scattering body, and reveal the effect of surface impedance on the absorption of the acoustic energy. Three test cases (i.e., the plane wave scattered by a rigid sphere, and the sound of the stationary monopole and dipole point sources scattered by an impedance sphere) are carried out to validate the method. From the analysis of the computational error, it is suggested that the maximum length of the surface element should be less than one-tenth of the wavelength to ensure that the relative error is less than 3%.