Schallfeldsimulation mit Spiegelquellen - Eine Planungshilfe für reflexionsarme Räume

Sound field simulation by image sources - A design tool for anechoic rooms.

Conventional designs of anechoic rooms according to ISO 3745 often bear risks since the usual assumption of an absorption coefficient at normal incidence of 99 % of traditional fibrous or porous claddings may be not necessary in one case but insufficient in another. A simulation program is presented which is based on the wave interferences of the sound from a real point source and a number of image sources which replace imperfectly absorbing bounding surfaces. Its application demonstrates various effects which can influence the free-field characteristics to the same extent as the absorption of the cladding. By this one may gain more confidence - at an early stage of the planning process - in the quality of an acoustic test facility for the determination of sound power, spectrum and directivity of technical sound sources.