The interpolated time-domain equivalent source method for modeling transient sound propagation in half space

Conventional interpolated time-domain equivalent source method (ITDESM) is based on the assumption of free space, which makes it not suitable for reconstructing the transient acoustic quantities in the half space. Here, two half-space ITDESMs are developed to model the transient sound propagation over a mass-like plane and an absorbing plane, respectively. By replacing the free-space transient Green's function in the conventional ITDESM with two half-space transient Green's functions, the sound reflection effects can be fully considered. Modeling acoustic radiation from the transient monopole sources above an infinite plane with mass-like and pure absorbing behaviour is, respectively, studied by numerical examples. Simulation results indicate that the proposed two methods can reconstruct the half-space transient sound fields in both the space and time domains very well. The feasibility and validity of both the half-space ITDESMs are experimentally verified via an impacted steel plate lying above a wooden table plate as well as a glass wool board in the semi-anechoic room.