中文摘要：

对某离心泵作透平流体诱发的内场噪声特性进行数值计算和试验研究。在典型流量下,采用雷诺时均方法获取壳体壁面偶极子声源,并利用边界元方法（Boundary element method,BEM）求解出壳体偶极子源作用的流动噪声,基于有限元结合边界元的声振耦合法（Finite element method/boundary element method,FEM/BEM）计算出流体激励结构振动产生的内场流激噪声及考虑结构振动的流动噪声,分析不同性质噪声源的频谱特性,同时评估内场声源在各个频段下的贡献量。借助水听器对透平出口进行流体声学试验,获得了噪声的频谱特性。结果表明,离心泵作透平出口流体诱发噪声主要集中在中低频段,小流量工况低频噪声特性增强。壳体声源作用下考虑结构振动流动噪声的计算结果与试验结果在较大流量下吻合较好。壳体偶极子作用的流动噪声对内场噪声的贡献最大,其次是考虑结构振动的流动噪声,流激噪声对内场噪声贡献最小。结构的影响使得二阶叶频处声压增加,其余离散频率及宽频处声压均有所降低。该研究结果为低噪声叶轮机械设计提供了一定的参考。

英文摘要：

The numerical simulation and experimental investigation are performed on flow-induced interior noise in a centrifugal pump as turbine（PAT）. Under typical flow conditions, the casing dipole source is obtained using Reynolds-average method. The flow-borne noise and flow-induced structure noise in interior acoustic field are solved by boundary element method（BEM） and finite element method/ boundary element method（FEM/BEM）, respectively. On the basis of this, the spectrum characteristics of each noise source and their contribution to interior noise are distinguished. Meanwhile, the noise spectra are evaluated by hydrophone placed at the outlet of PAT. The results show that the spectrum of flow-induced noise is mainly concentrated on low and medium frequency bands, with enhanced low-frequency spectrum behavior under small flow conditions. The spectrum versus frequency curve of flow-borne noise considering structure agrees well with experimental results, especially in larger flow conditions. The flow-borne noise is the biggest contributor to interior noise, followed by flow-borne noise considering structure, and the flow-induced structure noise is least. The structure increases sound pressure at second order blade passing frequency, lowers sound pressure at the rest discrete and broadband frequencies. The results can provide some reference for low noise design of similar turbomachinery.