%A LI Rennian, TAN Haiyan, LI Qifei, NIE Guokui, LIU Chaoª¤ %T Analysis of fluctuation characteristics at runner area of pump turbine %0 Journal Article %D 2015 %J Journal of Drainage and Irrigation Machinery Engin %R 10.3969/j.issn.1674-8530.14.0213 %P 1038-1043 %V 33 %N 12 %U {http://zzs.ujs.edu.cn/pgjx/CN/abstract/article_1965.shtml} %8 2015-12-25 %X In order to reveal the pressure fluctuation characteristics at the runner area of the pump turbine, pump turbine models were selected as the study object. Based on the Realizable k-¦Å turbulence model, three-dimensional unsteady numerical simulations were conducted and the pressure fluctuation characteristics of the runner were analyzed with part load under different conditions. The results show that when units with 30% load, the pressure fluctuation at the runner area becomes more severe with the head increasing. The pressure fluctuation characteristics at the upper canopy of the runner present periodic changes, and on the interface of runner outlet axis and the draft tube outlet the pressure fluctuation is in disorder in one cycle. The pressure fluctuation at the upper canopy of the runner increases from the inlet to the outlet, and its main frequency is the blade rotating passing frequency. The pressure fluctuation at the axis of the runner outlet is of low frequency and the amplitude decreases along the negative Z axis. The main frequency of pressure fluctuation on the interface of the runner and the draft tube decreases gradually with the head increasing, but the amplitude change is opposite.ª¤