Abstract:
Zhou et al. [J. Acoust. Soc. Am. 90, 2042--2054 (1987)] have hypothesized that mode conversion due to large-amplitude shallow-water internal waves (solitons) could explain the anomalous transmission loss observed in acoustic data taken in the Yellow Sea. Numerical experiments had been performed that substantiated their hypothesis [Chin-Bing et al., Math. Model. Sci. Comput. 4 (1994); King et al., Theor. Comput. Acoust. 2, 793--807 (1994)]. It is also found that the effect is most prominent when there is strong coupling between the lower-order propagation modes and the very lossy, higher-order modes. In reaching these conclusions, both groups assumed an idealized sinusoidal soliton structure. The analysis has recently been repeated using a soliton sound-speed structure more characteristic of what is found in straits. Results will be presented that show the similarities and differences in anomalous transmission loss for the realistic and the idealized sinusoidal soliton. [Work supported by ONR/NRL and by a Federal High Performance Computing DoD grant.]