舰船中低频结构噪声源识别方法研究

摘要

Because of the crucial role that ship hull structure plays in both source excitation and vibro-acoustical transmission of ship noises, source identification of ship hull structural noise was investigated in this paper.Coupled vibrations in ship structures, excited by machine-machine and propeller-shaft over low to medium frequency ranges, produce a multi-source correlated and multi-path coupling system.A model of low and medium frequency ship structural noise was established, considering the system features of correlated excitation, path coupling, and system uncertainties.A strategy for source identification of low and medium frequency structural noise was presented, based on statistical analysis of random system response, path transmission, and excitation sources.By employing that strategy, one can realize source identification of such noises from the standpoint of statistics, thus overcoming limitations in the existing methods of noise source identification for such problems as the random system vibration with multi-source correlation excitation and multi-path coupling vibration.This points out a direction for further study on noise source identification in ship structures, in theory and methodology.%考虑舰船壳体结构在舰船噪声的声源激励及声振传递中具有的重要作用，进行其结构噪声源识别研究。在中低频段内舰船壳体结构的机（械）－机（械）及桨轴激励船体耦合振动形成多源相关多通道耦合系统，考虑系统的相关激励、通道耦合、系统不确定性等特征，建立舰船中低频结构噪声模型，并基于随机动力系统响应、通道传递和激励源等统计分析提出中低频结构噪声源识别策略。提出的噪声源识别策略，以统计的观点实现中低频结构噪声系统的激励源识别，解决现有噪声源识别方法对于多源相关多通道耦合随机振动的局限性问题，并为舰船结构噪声源识别技术的进一步研究在理论、方法上指出探索方向。