3rd French conference on acoustics
J. Phys. IV France 04 (1994) C5-1055-C5-1058
Modélisation expérimentale et numérique de milieux marins réelsG. RABAU, J. PIRAUX, J. LEANDRE and R. HOLTZER
CNRS, Laboratoire de Mécanique et d'Acoustique, 31 Ch. J. Aiguier, 13402 Marseille cedex 20, France
In order to realize a complete geoacoustical model of the sea we have created a vertical variation in the sound velocity in a liquid layer presenting a minimum like in real sea by a diffusion technique in a tank. This technique involves the superimposing of several layers of miscible liquids with different densities without mixing. To simulate the sea bottom (with or without a 5 % slope) we have used two types of material - Polyurethane resin to represent a sedimentary ground and marble to represent an elastic rock. To account for the scale, the measures were made at a frequency of 1 MHz corresponding to 50 Hz in a real situation. The measured values are compared with the results of a numerical integration of the Helmholtz equation. We use a variant of the parabolic approximation.
© EDP Sciences 1994