不等间距分舱结构声辐射特性研究

研究舱段结构振动、声辐射特性随分舱形式改变的变化规律，对潜艇结构声学优化设计具有十分重要的意义。从结构声学设计的角度出发，在保持相邻两个舱段总长度不变的情况下，调整两个舱段的长度，采用结构有限元法、结构有限元耦合流体边界元方法，以辐射声功率、湿表面均方法向速度和辐射效率作为衡量结构噪声辐射能力的主要衡量指标，系统地研究整个结构振动和声辐射特性。在流体部分的计算中，采用网格重叠算法，以提高计算效率。通过调整分舱形式，在一定频段，改变了整个舱段结构振动声学传递函数的谱峰频率，降低了谱峰幅值，因此，可以通过改变分舱形式以改变舱段结构声学特性，使设备激振力的谱峰频率与结构振动声学传递函数的谱峰频率错开，实现对辐射噪声的控制。

Study on characteristics of acoustic radiation from the cabin structure with nonuniform subdivision

Study on the relation between the vibration and acoustic radiation from the cabin structures and the method of cabin division is very important for the structure-acoustic optimization design of the subma-rine. From the angle of the structure-acoustic design, in the condition of keeping the total length of two cabins, adjusting the length of the two cabins respectively, and the structural finite element method, and the structural finite element coupled fluid boundary element method are adopted for the numerical calcula-tion, and the acoustic radiation power, mean square normal velocities of the wet surface and the acoustic ra-diation efficiency are adopted as the main indexes to estimate the acoustic radiation ability from the sub-routine structures and the characteristics of the vibration and acoustic radiation from the whole structure systemically. In the calculation about the fluid, the ‘mesh superposition method’ is used to improve the calculating efficiency. By adjusting the cabin division method, in some frequency band, the peak value fre-quencies of the transfer functions of the vibration and acoustic radiation are changed, and the peak value is reduced. The results show that the acoustic characteristics of the cabin structure can be changed by adjust-ing the above method, so that the exciting force of the machines and the spectral peak frequencies of the transfer functions are separated, as a result, the noise and vibration are controlled.