抽水蓄能电站输水发电系统一般埋深较大,在引水系统外水内渗的作用下,厂房洞室群三维渗流场分布复杂,排水措施对控制输水发电系统的渗流场具有重要作用。采用三维渗流场有限元方法,建立张掖抽水蓄能电站输水发电系统三维渗流场数值计算模型,真实考虑输水系统、地下厂房系统、防渗排水系统。在对抽水蓄能电站输水发电系统的渗流场分布规律进行分析的基础上,讨论了压力管道下层排水系统和厂房排水系统对渗流场的影响。 结果表明: 正常运行情况下,地下厂房大部分位于浸润线以上且在设计渗控方案下渗流量控制在合理范围之内,渗流在靠近厂房洞室群的底部溢出,管道表现出内水外渗的特点,尾水系统渗流量相对较大;压力管道下层排水廊道对压力管道和厂房上游侧渗流场产生较大的影响,排水孔间距越小浸润线越低且相应区域渗流量越大,排水孔间距为3 m较为合理;厂房区域排水系统对地下厂房渗流场影响显著,随着排水孔间距的增加,排水效果减弱,集水井内流量减少,浸润线有所抬升,排水孔间距为3 m较为合理。

The water conveyance and power generation system of pumped storage power stations is generally buried deeply,and the three-dimensional seepage field distribution of the plant’s chamber group is complex due to external seepage in the water diversion system. Drainage measures are crucial in controlling the seepage field of water transmission and power generation system. Using the three-dimensional seepage field finite element method, we constructed a numerical calculation model of Zhangye pumped storage power station’s water delivery and power generation system, integrating the water conveyance system, underground plant system, and seepage prevention and drainage systems. Based on the distribution law of seepage field within the power generation system, we analyzed the impact of the drainage system beneath the pressure pipeline and the plant’s drainage system on the seepage field. Results indicate that under normal operating conditions, most of the underground plant is above the wetting line, and seepage flow is maintained within a reasonable range under the designed seepage control plan. Seepage overflows occur near the bottom of the plant chamber group, the pipeline exhibits characteristics of internal water seepage, and the seepage flow of the tailwater system is relatively large. The lower drainage gallery of the pressure pipe significantly influences the seepage field of the pressure pipe and the upstream side of the plant. A smaller drainage hole spacing results in a lower wetting line and larger seepage flow in the corresponding area, with a drainage hole spacing of 3 m proving more reasonable. The drainage system in the plant area significantly affects the seepage field of the underground plant. As the drainage hole spacing increases, the drainage effect diminishes, the flow into the collection well decreases, the wetting line rises slightly, and a drainage hole spacing of 3 m is deemed more reasonable.