离心泵流动诱发振动特性数值计算分析

建立了一种适用于离心泵等叶轮机械流动诱发振动工程计算的数值模型和方法流程。基于URANS方程求解泵内流场，在流场非定常计算过程中输出叶轮所受时域脉动压力，将脉动压力通过FFT转换到频谱并以之作为泵组结构的振动激励源，采用隐式有限元方法进行泵组结构振动响应的计算。计算方法通过测试得到验证，可以用于离心泵流动诱发振动特性的计算评估和低噪声设计。完成了原型和改进型船用海水泵在设计工况下流动诱发振动响应的计算，分析了两型泵流场、振动激励源和振动响应等特性。计算表明，泵的改型设计显著减小泵内压力脉动以及振动激励源，改型泵振动小于原泵。

Numerical analysis for flow induced vibration of a centrifugal pump

A simulation method for flow-induced mechanical vibrations in a centrifugal pump used in a ship was presented here.The interior flow field was simulated with an URANS-based CFD program.The pressure fluctuations on blades of an impeller were exported using UDF interface program,the time series of pressure fluctuations on the external surface were provided as force-boundary conditions.The vibration exciting source was obtained by integrating pressure fluctuations on the bearing of the impeller and using fast Flourier transformation.The vibrations of the pump and the motor system were simulated using a standard dynamic FE code in frequency domain.The experimental results showed that the numerical method can be used to estimate flow-induced vibration generated in a turbo-machinery and to design a low-noise centrifugal pump.The numerical results of the proposed method showed that the improved type of pump is better than the original type of pump.