Study On Sound Propagation Through A Mesoscale Eddy Environment

The effect of the mesoscale eddy on sound propagation has already attracted wide attention from the whole acoustic field since the late 70’s. Compared with the offshore environment, deep sea environment is less likely to be affected by environmental factors, which has stable temperature and salinity structures. Up till the present moment, due to detect is inconvenient and some other reasons, there is not have a thorough study on the relationship between mesoscale structure and sound propagation characteristics. By analyzing the effect of the mesoscale eddy on sound propagation qualitatively and quantitatively, the effect of Marine mesoscale eddy structure of sound field on sound propagation can be gained, which has profound meaning on inversion of sound field environment, communication of deep sea channel and detection of Marine information.This article refer to the actual each parameter that the mesoscale vortex in the northwestern Pacific and south China sea, cold eddy gaussian model, analysis of cold eddy parameter change on the impact of sound propagation; Mesoscale vortex effect on sound propagation in previous based on qualitative analysis, using SPSS statistical analysis software of convergence area of a cold eddy environment parameters sensitivity analysis, the results show that the acoustic field in a cold eddy environment gathering area span is reduced, and its change with cold eddy parameter changes linearly.The article also discussed the relation between ray and the normal mode theory. Analysis of the waveguide invariant and ray stability parameters of the relationship between two quantities are equal. And simulation analysis in the presence of a cold eddy ray and the normal mode when long-distance transmission stability, and the results show that ray and the normal mode when only considering the aquatic environment change is relatively consistent results. In the deep sea environment is often due to normal mode number too much waveguide invariant, in the case of plane can’t extract, ray stability parameter from another Angle reflects the change of the Marine environment, and is used to research of sound propagation characteristics.Numerical assimilation results obtained in this article, at the same time use ocean thermohaline distribution analysis of the south China sea environment graded situations ray stability parameter change rule, the results show that the radiation stability parameter in the presence of a cold eddy when a significant change, and its change rule and the sound velocity field change perfectly.