水下航行器空化噪声偏度和峰度分析

空化是水下高速航行器在进行总体设计时需要考虑的重要因素。对空化产生的噪声特性进行研究有助于水下航行器航行性能和目标检测能力的提高。文章首先介绍了空化噪声的形成机理和数学模型，然后基于实测数据对空化噪声相应的统计特性进行了分析，计算了典型的单个声脉冲形式的空化噪声的概率分布、偏度和峰度，对比分析了无空化发生与空化发展比较充分条件下实测空化噪声的偏度和峰度特性。结果表明，在空化充分发展时水下航行器空化噪声具有明显的非高斯特性，其偏度和峰度值明显大于理想高斯噪声或者实际的海洋环境噪声。有利于提高空化条件下水下航行器对目标辐射噪声检测的准确性以及检测系统的环境适应能力。

Skewness and kurtosis analysis of cavitation noise for underwater vehicles

Cavitation is an important factor in the overall design of high-speed underwater vehicle. The research on the characteristics of cavitation noise is helpful to improve the navigation performance and enhance the target detection ability of underwater vehicle. In this paper, the formation mechanism and mathematical model of cavitation noise are introduced firstly. Then, the statistical characteristics of cavitation noise are analyzed based on measured data, the probability distribution, skewness and kurtosis of the typical cavitation noise in the form of an individual acoustic pulse are calculated, and the skewness and kurtosis of cavitation noise under different conditions of no cavitation and fully developed cavitation are compared and analyzed. The results show that the cavitation noise of underwater vehicle has obvious non Gaussian characteristics when the cavitation is fully developed, and its skewness and kurtosis are significantly greater than those of Gaussian noise or the actual marine ambient noise. It is beneficial for the underwater vehicle to improve the accuracy of target radiated noise detection and the environmental adaptability of detection system under cavitation condition.