流固耦合作用下的注水管路流激振动噪声数值模拟

大压差工况下,船舶内部液舱自流注水时管路振动噪声问题突出。采用有限体积法离散大涡模拟的流体控制方程,计算分析典型工况下注水系统管内流场。考虑管内液体对管道结构振动的影响,计算注水管路的“湿模态”。以管路壁面流体压力脉动作为激励源,基于有限元法对流固耦合作用下管道结构的振动和流激振动辐射噪声进行数值模拟。对阀门上下游不同监测点的流激振动噪声频谱进行分析,探究管路流激振动噪声产生、传播和衰减规律。分析结果表明:注水系统管道结构流激振动噪声沿管道传播基本无衰减;流激振动噪声频带较宽,主频率为80 Hz;管道结构的流激振动噪声整体幅值较大,需要采取增加弹性管卡等措施进行治理。

Numerical simulation study on flow induced vibration noise of ship water injection pipeline based on fluid structure interaction

Under large pressure difference condition,the vibration and noise of ship water injection system are outstanding.Fluid control equations for large eddy simulations were discretized using FVM.The flow field was calculated under typical working conditions.Considering the liquid influence on the vibration of pipeline structure,the structure wet mode was calculated.Taking the fluid pressure fluctuation at the wall of the pipeline as an excitation source,the pipe structure vibration and radiation noise were calculated based on FEM.The noise spectrums of different upstream and downstream monitoring points were analyzed to probe into the laws of generation,propagation and attenuation.The results show that the noise is basically undammed along the pipeline.The noise band is wide and the main frequency is 80Hz.The noise amplitude is large.Measures like putting up more elastic pipe clamps need to be taken.