Acoustic Field Excited by a Supersonic Source in a Two Media Configuration.

摘要

The acoustic wave field due to a supersonic motion of a rigid object over a half-space is investigated. The research presented here is of great importance for the modeling of the transmitted and reflected conical waves that are excited by airplanes that fly over sea or land. The media involved are acoustically modeled as homogeneous, isotropic fluids and the moving object is represented an acoustic source of the dipole type. The linearized acoustic field equations are applied to obtain representations for the fields in a combined Laplace-Fourier transform domain. To these representations, which are mapped into the proper form, the authors apply the Cagniard-de Hoop technique in order to find closed form time-domain solutions for the reflected and transmitted acoustic fields. Special wave phenomena, like head waves and reflected and transmitted conical waves, come forward from the procedure as partial result with precursive fronts and clearly defined trailing edges. Numerical results for the reflected as well as the transmitted conical wave are presented.