RAY THEORY APPLIED TO THE INTER CAUSTIC IDENTIFICATION OF LIQUID CAVITIES ACOUSTICALLY INSONIFIED

The acoustic field in water-filled cylindrical cavities machined insid e a duraluminum matrix is studied. The internal acoustic beam focused near the cusp points within the liquid cavity. An optical process (pul sed schlieren technique) is used to, visualize the acoustic wave front as the wave propagates in the fluid cylinder. The axial positions of the p-ray cusp caustics are compared with the theoretical values calcu lated by the ray theory [J. A. Lock and E. A.Hovenac, J. Opt. Soc. Am. A 8, 1 541-1552 (1991)].