Research On Acoustic Radiation Characteristics Based On Element Radiation Superposition Method For Underwater Cylindrical Shell

It is well known that the concealment of submarine is of great importance to enhance the combat effectiveness and safety of the submarine.Only real-time and fast prediction of the radiation noise of the submarine during service can more effectively take corresponding measures to control and reduce the radiation noise so as to improve the submarine's concealment.There are many methods to predict the radiation noise,and the analytical method is only applicable to the analysis and calculation of simple structures,and the classical numerical calculation method represented by the boundary element method has its unavoidable defects.Therefore,it is urgent to find an accurate and fast method for the calculation of radiation field.This paper solves this problem well by using the method of unit radiation superposition.But according to the analysis,in the process of using the unit method of superposition of radiation,if and when the structure dimension and acoustic wavelength can be compared to sound field of a major contribution unit cannot be rule mask good timeliness,prediction error will be bigger.Therefore,we can use this method to predict the radiation sound field as long as the units that contribute to the sound field can be fitted with the regular shape baffle.In this paper,the basic principle of unit radiation superposition method is introduced,and the feasibility of this method is explained.Then,with the model of the cylindrical module,Matlab is used to program,and the calculated results are compared with the result of the analytical method and COMSOL simulation results to verify the accuracy of the unit radiation superposition method.Because we often need to be considered in practical projects within a band of incentive motivation rather than just a single frequency,therefore,also studied the broadband excitation radiation acoustic field of compartment model,and under the condition of lack of phase and phase information to carry under the conditions of both calculated by the radiated acoustic field are compared.Finally,the contribution of the piston to the total radiation sound field is simulated and analyzed in the case of different excitation frequencies.The simulation results of the study shows that the unit of radiation superposition method and the analytic method of the simulation results are in good agreement,so using the unit method of superposition of radiation of compartment model of underwater radiated acoustic field of forecast is feasible.In addition,the same cylindrical shell model,using COMSOL software calculated results are consistent with the result of the superposition method and the basic unit radiation,once again to verify the unit the accuracy of the method of superposition of radiation,at the same time,we can directly use COMSOL calculation results to predict the radiation sound field.For different excitation frequency range,the surface of the cylindrical shell's contribution to the radiation sound field is also different,we can according to the actual situation and needs,to choose the appropriate piston on the surface of the cylindrical shell to calculate,do not need to calculate all the piston's contribution to the radiation sound field surface,thus greatly improving the calculation efficiency.