基于有限数据的水下球类目标多基地低频散射声场预报方法

Prediction Method of the Low-Frequency Multistatic Scattering Sound Field for Underwater Spherical Targets Based on Limited Data

针对水下球类目标多基地声散射声场预报,提出了一种基于有限散射声压信息数据的预报方法.该方法将散射声场表示为声散射传递函数与声源密度函数的乘积形式,通过数值积分以模型表面网格信息作为输入得到声散射传递函数,以已知的少量散射声压数据作为输入,综合运用声学互易性、最小二乘法和矩阵变换得到声源密度函数.针对双层球壳以及带铺板球壳,分别利用Rayleigh简正级数解和有限元计算方法对该预报方法进行了验证.对带铺板球壳进行了目标强度试验,对比了测试结果和有限元计算结果,分别以几个测试数据和有限元数据作为输入预报了带铺板球壳多基地散射声场并与有限元结果对比.仿真和试验结果均吻合较好,验证了该预报方法的可行性.

A prediction method based on the information data of finite scattering acoustic pressure is proposed for the prediction of underwater spherical target multistatic acoustic scattering sound field,which represents the scattering sound field as the product of the acoustic scattering transfer function and the source density function,obtains the acoustic scattering transfer function by numerical integration with the model surface grid information as input,and acquires the source density function by combining acoustic reciprocity,least squares,and matrix transformation with small amount of known scattered sound pressure data as input.The multistatic scattering sound field prediction method is validated by using the Rayleigh normal mode solution and the finite element method(FEM)for double-layered spherical shells and spherical shell with the stiffener.The target strength experiment is conducted for the spherical shell with the stiffener,and the experiment results are compared with the finite element calculations.Several test data and FEM calculation results data are used as input to predict the multistatic scattering sound field of the spherical shell with stiffener and compared with the FEM results,respectively.It is found that the simulation and test results are in good agreement,which verifies the feasibility of the prediction method.