舰船螺旋桨空化噪声建模与仿真研究

为了解决螺旋桨空化噪声的连续谱及其调制谱特性的建模与仿真问题,在对空化噪声 连续谱理论研究和实验分析的基础上,依据各空泡的崩溃时刻的随机性和准周期性及其辐射噪声 的波形结构,分4 种情况分别对各空泡辐射噪声的合成功率谱进行了理论分析,并进行了仿真验 证,提出了空化噪声连续谱的时域蒙特卡罗仿真模型;结合螺旋桨空化噪声时变特性的物理机理, 提出了螺旋桨空化噪声调制波形仿真算法。理论分析和仿真结果表明,螺旋桨空化噪声调制特性 频域不均匀性本质是空化噪声连续谱形状的不稳定性造成的。

Modeling and Simulation of Vessel Propeller Cavitation Noise

In order to solve the problem of modeling and simulation of continuous spectrum of propeller cavitation noise and its modulation spectrum characteristics, four circumstances are categorized to conduct theoretical analysis on synthetic power spectrum of each cavitation bubble noise, and to perform simula- tion tests based on theoretical study and test results on cavitation noise continuous spectrum, randomicity, psuedo - periodicity of collapse of each cavitation bubble, and the waveform of its radiated noise, during which time domain Monte Carlo simulation model is proposed for cavitation noise continuous spectrum. The theoretical analysis and simulation results both show that the frequency domain offset of propeller cav- itation noise modulation characteristics is resulted from instability of cavitation noise continuous spectrum shapes.