基于表面响应预报水下圆柱壳声辐射的振动测点布置研究

摘要

A method of transducer arrangements based on BEM is presented in this paper. Firstly,study the amount of transducers of cylindrical shell in axis and circumference directions,then,the optimum transducer arrangement is determined by comparing the prediction accuracy of the radiated sound power under different transducer arrangements. The results show that between 10 Hz and 125 Hz,the optimum numbers of transducers for axial and circumferential directions of a given modal are 5 and 12,respectively. It should be noted that while increasing the number of transducers above the optimum value does not signif⁃icantly improve the sound power prediction accuracy,choosing a number lower than the optimum value does induce considerable calculation error. Also,this method is only applicable for low frequencies,and the distance between transducers can be confirmed with the corresponding 1/6 wavelength.%　　针对基于表面振动的圆柱壳声辐射估算的测点布置问题,提出均匀的测点布置方法。利用有限元法计算大尺度单层加肋圆柱壳在水下振动时的表面速度分布,根据边界元法及各测点处的速度计算不同测点布置对应的辐射声功率,比较各振动测点布置对应的声辐射预测精度,选择合理的测点布置。计算结果表明,对于给定尺寸的结构,在10~125 Hz 范围内,周向和轴向测点数存在最优值(周向12个、轴向5个),当测点数大于最优值时,测点数量的增加不能有效提高声功率的计算精度；当测点数小于最优值时,声功率的计算误差明显增大。在较低的频率范围内,1/6声学波长可作为大尺度结构在水下振动时的测点布置依据。