ANALYSIS OF A RIGID FRAME MODEL OF POROUS-MEDIA FOR THE ACOUSTIC PROPERTIES OF DENSE SNOW

Acoustic impedances of dense snow samples have been measured with the two-microphone impedance measurement tube method developed by Chung an d Blaser [1]. The parameters (h, k, R) of the rigid frame model propos ed by Zwikker and Kosten [2] were used successfully by Buser [3] for r ather light snow (rho less than or equal to 400 kg/m(3)). However, for dense snow, the measurements indicate a great deviation from theory, especially for high frequencies. This difference is not reduced by usi ng the new parameter lambda(app) (apparent thermal conductivity) intro duced by Zwikker and Kosten for a granular medium (see reference [2], pp. 25-48). (C) 1996 Academic Press Limited.