ASA 125th Meeting Ottawa 1993 May

3aSA13. Radiation and propagation properties of elastic waves on conical shells.

Y. P. Guo

Dept. of Ocean Eng., Rm. 5-204, MIT, Cambridge, MA 02139

This talk discusses the radiation and propagation properties of elastic waves on conical shells by making use of a previously developed theory [Y. P. Guo, J. Acoust. Soc. Am. 92, 2388 (A) (1992)]. The three types of dominant waves in the mid-frequency domain, namely, the compressional, shear, and flexural waves are examined. It is shown that when propagating toward the apex of the cone, shear waves are turned back at caustics but compressional waves are cut off only where they have become subsonic. The radiation losses of these waves are also discussed. It is found that compressional waves radiate much more efficiently than shear waves on a cone, indicating that much less compressional wave energy would be reflected by a cone-shaped endcap. This is indeed what was observed in these scattering experiments.