调整段作为抽水蓄能电站侧式进/出水口的重要组成部分,其长短直接影响到进/出水口双向过流条件下的水力特性及工程造价,因此开展相关研究具有重要意义。在两河口抽蓄电站侧式进/出水口体型的基础上,分析了调整段长度对侧式进/出水口水力特性的影响规律。结果表明:①发电工况(出流)下,调整段长度的增加,可降低进/出水口水头损失,均化拦污栅断面流速;抽水工况(进流)下,调整段长度的增加,可降低进/出水口水头损失。②当调整段长度L与扩散段长度T满足L≥0.3T时,进/出水口双向过流的水力特性较好;当0.1T≤L<0.3T时,进/出水口双向过流水力特性略差但满足规范设计要求。研究成果可为调整段的设计及优化提供支撑。

[Objective] As an important part of the side inlet/outlet of a pumped storage power station, the length of the adjustment section directly affects the hydraulic characteristics of the inlet/outlet under bidirectional flow conditions as well as the project cost. This paper aims to investigate the effect of different adjustment section lengths on the hydraulic characteristics of side inlet/outlet, focusing on changes in head loss, velocity distribution, and discharge allocation, and to recommend an appropriate range of adjustment section lengths that meets design codes. [Methods] A three-dimensional mathematical model of the side inlet/outlet of the Lianghekou pumped storage power station was established. The Reynolds Stress Model (RSM) was adopted and validated against physical model test results. The velocity curves obtained from numerical simulation showed good agreement with the experimental measurements, confirming the applicability of the selected turbulence model to the study of inlet/outlet hydraulic characteristics. [Results] For the power generation condition (outflow), increasing the adjustment section length reduced inlet/outlet head loss, homogenized the velocity distribution at the trash rack section, and kept the discharge non-uniformity across openings within 5%. For the pumping condition (inflow), increasing the adjustment section length also reduced inlet/outlet head loss and maintained discharge non-uniformity within 10%. When the adjustment section length L relative to the diffusion section length T satisfied L≥0.3T, the bidirectional hydraulic characteristics of the inlet/outlet were favorable; when 0.1T≤L<0.3T, the bidirectional hydraulic characteristics were slightly poorer but still met code design requirements. [Conclusion] The research results provide support for the design and optimization of adjustment sections.