Abstract: Underwater mechanical noise is one of the main noise sources of submarines. In this paper, the transfer paths of radiation noises of mechanical equipments of the submarines are analyzed, and the procedure from shell vibration to radiation noise prediction is studied theoretically and experimentally. Distribution of vibration acceleration of the inner and outer shells is measured by model testing. The mean-square vibration velocity of the inner and outer shells is computed. With sub-band radiation efficiency formula of stiffened cylindrical shell, the values of radiation sound pressure are predicted using the mean-square vibration velocities of the inner-and-outer shells. The results are compared with the experimental data. It shows that the computation and experimental results are in good agreement. It is concluded that only the inner-shell vibration signal is necessary for prediction of radiation noise of the double-layer shell structure. Therefore, the feasibility of radiation noise prediction through the shell structural vibration is demonstrated.

Key words: acoustics, compartment structure, mean-square velocity, radiation efficiency, estimation

摘要： 机械噪声是水下航行器主要噪声源之一。首先分析机械设备辐射噪声的整个传递途径，然后就壳体振动到辐射噪声预报环节展开理论和实验研究。通过模型实验测得内外壳结构振动加速度分布，经过计算分别获得内外壳结构振动均方速度，结合加肋圆柱壳分频段辐射效率公式，分别采用内外壳结构振动均方速度对结构辐射声压进行预报计算，并与实验结果进行对比分析。分析表明计算结果与试验吻合良好，得出对于双壳体结构，可由内壳体结构振动预报辐射噪声的结论，验证通过壳体结构振动预报辐射噪声方法的可行性，该方法具有较好的工程应用价值。

关键词: 声学, 舱段结构, 均方速度, 辐射效率, 估算