声场匹配波叠加法的水下结构声辐射预报

提出了一种适用于典型结构声辐射预报的声场匹配波叠加方法。该方法利用少量的参考点声压,通过声场匹配搜索等效源分布,得到最小二乘意义下的最优等效源位置。并研究了表面振动测点位置、数目及振动分布的离散性对声场预报精度的影响。最后在半空间消声水池中,对两端带帽圆柱壳的声辐射预报进行了试验验证。结果表明:等效源最佳位置一经确定,即可利用结构的表面振速,对不同激励下的该结构进行声辐射预报。该方法在较宽频段内对不同的振动分布有较好的适应性。 

Sound radiation prediction for underwater structure by field-matching wave superposition method

A field-matching wave superposition method for sound prediction of typical structures is proposed.The method partially base on least square method(LSM),in which a few reference points of sound pressure should be measured ahead to search the optimal position of equivalent sources.Moreover,the effects of the number,position of measuring points and amplitude distribution of vibration were studied numerically.In order to prove the efficiency of this method,an experiment for predicting sound radiation from a cylindrical shell with hemi-cap has been done successfully in a half-space anechoic tank.The result shows that the sound radiation of a structure,for different excitations,can be predicted precisely from surface velocity by wave superposition method once the optimal position of equivalent sources is determined by LSM using the sound pressure of reference points.The method has a considerable adaptability for different frequency and vibration distribution.