水泵水轮机泵工况旋转失速压力脉动特性及转动机理

发布时间：2018-06-09 14:36

本文选题：水泵水轮机 + 旋转失速　；参考：《水利学报》2017年07期

【摘要】：水泵水轮机在泵工况部分负荷下运行,叶道内易发生旋转失速,可诱发剧烈的低频压力脉动,严重影响水电站的安全稳定运行。本文采用尺度自适应(SST-SAS)湍流模型对某模型水泵水轮机泵工况进行全流道非定常数值模拟,得到不同工况点下旋转失速引起的压力脉动特性及失速涡团的周向转动机理。结果显示,在40%~80%设计流量下运行时,导叶区发生旋转失速,失速涡团的转动频率为叶轮转频的3.3%~8.1%。旋转失速发展强度越剧烈,转动越慢。旋转失速周向转动的机理是:失速与非失速相邻导叶流道内存在较大压力梯度,在其作用下,失速流道内流体从活动导叶与固定导叶之间通道流向非失速流道,加剧非失速流道内流动分离。被阻碍的水流与无叶区主流叠加流向下一流道,并在活动导叶吸力面进口前缘产生局部低压,导致当前非失速活动导叶流道在进口与出口之间的逆压梯度增强,使流体反向流动,流道产生失速。
[Abstract]:When the pump turbine operates under the partial load of the pump condition, the rotating stall is easy to occur in the impeller duct, which can induce severe low frequency pressure pulsation and seriously affect the safe and stable operation of the hydropower station. In this paper, the full-channel unsteady numerical simulation of a model pump is carried out by using the scale adaptive SST-SAS turbulence model, and the pressure pulsation characteristics and the circumferential rotation mechanism of the stall vortex mass are obtained at different working conditions. The results show that when running at 40% of the designed flow rate, the rotating stall occurs in the guide vane area, and the rotational frequency of the stall vortex mass is 3.3% and 8.1% of the rotating frequency of the impeller. The more intense the rotating stall, the slower the rotation. The mechanism of circumferential rotation of rotating stall is as follows: there is a large pressure gradient in the channel of the stall and non-stall adjacent guide vane, under which the flow in the stall passage flows from the channel between the moving guide vane and the fixed guide vane to the non-stall channel. Aggravation of flow separation in non-stall channels. The blocked flow superposed with the mainstream of the leafless zone to the next channel and produced a local low pressure at the leading edge of the inlet of the suction surface of the active guide vane, resulting in an increase in the reverse pressure gradient between the inlet and outlet of the current non-stall active guide vane channel. Causes the fluid to flow backward, the passage produces the stall.
【作者单位】：重庆交通大学西南水运工程科学研究所;武汉大学水资源与水电科学国家重点实验室;
【基金】：国家自然科学基金面上项目(51579187) 重庆市基础与前沿研究计划项目(cstc2016jcyj A1935,cstc2016jcyj A1937) 重庆市教委科学技术研究项目(KJ1600514,KJ1600535) 重庆交通大学内河航道整治技术交通行业重点实验室开放基金重点项目(NHHD-201501,NHHD-201505,NHHD-201513)
【分类号】：TV675

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