基于CFD的TBL脉动压力水下航行器流激噪声计算

Flow-induced Noise of Underwater Vehicles Calculation Based on CFD and The turbulent Boundary Layer Pulsating Pressure

摘要:

高速航行时的水下航行器的水动力噪声问题一直尤为突出。其中,水动力噪声分为流体脉动压力直接辐射声与流激噪声。流激噪声是结构表面受到湍流脉动压力引起结构振动产生的噪声。由于湍流扰动的随机性,表面脉动压力时空不均,在计算流激噪声时需要统计分析方法的介入。湍流边界层脉动压力的计算方法主要包括传统的半经验公式法计算和CFD流场分析计算。将二者相结合对流激噪声进行预报,在流场仿真中提取出频率波数谱预测模型所需的参数,分别使用有限元法和统计能量法代入并计算,对比结果与理论经验公式方法得到的结果,二者的噪声结果较为吻合

Abstract:

The hydrodynamic noise issue of underwater vehicles during high-speed navigation has always been particularly prominent. Among them, hydrodynamic noise is divided into fluid pulsation pressure direct radiation noise and flow-induced noise. Flow-induced noise is the noise generated by structural vibration caused by turbulent pulsation pressure acting on the structural surface. Due to the randomness of turbulent disturbances, the spatial-temporal unevenness of surface pulsation pressure requires the intervention of statistical analysis methods when calculating flow-induced noise. The calculation methods for turbulent boundary layer pulsation pressure mainly include traditional semi-empirical formula calculation and CFD flow field analysis calculation. Flow-induced Noise calculation uses method combined with these two, extracting the parameters required for the frequency wavenumber spectrum prediction model in flow field simulation, and respectively using the finite element method and statistical energy method for calculation. The results are compared with those obtained from theoretical empirical formula methods, and the noise results of the two are quite consistent.