贯流式水轮机压力脉动特性及尾水管流态分析

Analysis of Pressure Pulsation Characteristics of Tubular Turbine and Draft Tube Flow Pattern

本文以福建高唐水电站灯泡贯流式水轮机真机为研究对象,对贯流式水轮机满负荷工况、额定工况和低负荷工况进行了三维非定常数值模拟,各工况导、桨叶均为各自对应的最优协联角度,来分别研究三种工况压力脉动特性和尾水管的流动情况。结果表明,灯泡贯流式水轮机在导叶进口、转轮进口和尾水管进口压力脉动主要是受叶片通过频率影响,即由转轮旋转所引起的,而在尾水管出口主要受低频压力脉动的影响。同时,满负荷工况时,脉动幅值最小,尾水管流线相对分布均匀,形成的涡量最少,额定工况至低负荷工况,幅值越来越大,尾水管流线也越来越紊乱,漩涡数量明显增加。

This paper takes the real bulb tubular turbine of Fujian Gaotang Hydropower Station as the research object,and simulates the full load,rated and low load conditions of the tubular turbine.They are all corresponding optimal association angles to study the pressure pulsation characteristics of the three working conditions and the flow of the draft tube.The results show that the pressure pulsation at the guide vane inlet,runner inlet and draft tube inlet of the bulb tubular turbine is mainly affected by the passing frequency of the blades,that is,caused by the rotation of the runner,while the draft tube outlet is mainly affected by low-frequency pressure pulsation.Influence.At the same time,under full load conditions,the pulsation amplitude is the smallest,the draft tube streamlines are relatively evenly distributed,and the vorticity formed is the least.From the rated operating conditions to the low load conditions,the amplitude becomes larger and the draft tube streamlines also increase.The more disordered,the number of vortices increases significantly.