中文摘要：

为了降低液力透平蜗壳内的压力脉动幅值,选择一单级离心泵为研究对象,当离心泵反转作液力透平时,在液力透平叶轮进口前添加一组固定导叶,利用Pro/E软件建立添加导叶前后的几何模型,然后利用软件ANSYSCFD计算两模型蜗壳内周向、径向以及不同流量下的压力和压力脉动变化情况,并通过快速傅里叶变换将压力脉动的计算结果进行处理,分析蜗壳内的时域和频域分布.研究发现：叶轮进口前添加导叶可有效降低蜗壳内周向和径向最大压力脉动幅值,且使大流量下蜗壳内的压力脉动幅值增加程度降低.

英文摘要：

In order to reduce the amplitude of pressure fluctuation within volute of hydraulic turbine,a single-stage centrifugal pump was selected to operate as a hydraulic turbine and a set of stationary guide vanes was supplemented in front of impeller inlet of hydraulic turbine.The geometric models of hydraulic turbine before and after guide vane supplementing were established by using software Pro/E,and the change of circumferential and radial pressure and its fluctuation in the volute of the models were calculated by using software ANSYS-CFD.Then the calculation result of the change of pressure fluctuation was processed with rapid Fourier transformation in the case of different flow rates and the distribution of time domain and frequency domain in the volute were analyzed.It was found by the investigation that the circumferential and radial amplitude of pressure fluctuation in volute could be effectively reduced by supplementing guide vanes in front of impeller inlet of hydraulic turbine and the degree of increase of pressure fluctuation amplitude in volute could also be decreased in the case of large flow.