Optimization Of Sound Absorption Performance Of Underwater Composite Structure

Laying sound absorption layer in the submarine surface can effectively absorb the active sonar emission of sound waves,thereby reducing the echo intensity,enhance the submarine stealth performance.With the progress of underwater acoustic detection equipment,the submarine sound stealth performance also need to be further improved.Therefore,this paper studies the sound absorption performance of the composite structure of the rubber plate with the cylindrical cavity structure and the porous metal material.Firstly,the calculation formula of the sound absorption coefficient for the double layer and the three layers cavity rubber absorber is deduced by using the propagation characteristics of the acoustic wave in the sound absorbing layer of the layered material and the cylindrical cavity.According to the calculation result,the sound absorption performance of the sound absorber under different layers was been analyzed with the change of the cavity size and thickness.Then,the propagation characteristics of the acoustic wave in the porous metal material are introduced,and the curve of the sound absorption coefficient of the composite body with the rubber sheet and the porous metal material is calculated,the sound absorption performance of the composite sound absorbers was improved obviously in the low frequency range.Finally,under the premise that the thickness and the size of the rubber layer are equal,compared the sound absorption capacity of the rubber sound absorber and the composite sound absorber,the results show that the sound absorber with the porous metal layer has good overall sound absorption performance.Because the sound absorption performance of the composite structure is affected by many structural parameters.In order to make the average sound absorption coefficient of the sound absorber to achieve the maximum,the multi-population genetic algorithm is used to optimize the cavity size and thickness of the composite structure to find the best combination.Then using MATLAB to get the optimal combination of parameters to verify the calculation,the results show that the composite structure of the composite structure with multi-population genetic algorithm has better sound absorption performance in the set frequency range,whether it is the whole optimization or the local low frequency optimization.