Radiation of moving sources in time-domain simulations of outdoor sound propagation

Invited paper

LMFA, Ecole Centrale de Lyon

Monday 1 june, 2015, 11:20 - 11:40

0.7 Lisbon (47)

Abstract:

This paper is concerned with time-domain simulations of radiation of moving sources in complex outdoor environments. Indeed, time-domain methods are well-adapted to study the radation of moving sources as they can handle any source trajectory and any variation of the source speed during its motion. First, the case of a source moving at a constant height and at a constant speed above a flat ground is examined. For a perfectly reflecting ground, the numerical solution is compared with an analytical solution. Results are then examined for finite-impedance grounds. A comparison is performed with an analytical solution proposed for a constant surface impedance, showing that the frequency-variation of the surface impedance must be accounted for. In all cases, the Doppler shift is retrieved. At last, radiation of a moving source above a complex terrain is studied. The topography corresponds to that measured during an experimental campaign carried out in May 2010. The effects of a topographic accident on the pressure field are examined.