进出水口双向流动结构流速分布与脉动规律研究

抽水蓄能电站水道系统侧式进出水口因内部分流隔墩等导致流动复杂，其内部双向流动规律尚不清晰。本文以某实际工程进出水口为基础建立典型进出水口试验装置，利用先进的流速量测仪器进行试验研究。基于粒子图像测速技术（PIV）量测结果，揭示了侧式进出水口内部双向流动规律，出流工况，中孔扩散段内形成明显的主流且位于孔口中部，扩散段及调整段顶部形成低流速区，边孔扩散段内主流不明显；进流工况，中孔及边孔调整段顶部存在低流速区，水流汇入扩散段后流速分布趋于均匀。基于声学多普勒测速技术（ADV）量测结果，揭示了拦污栅断面脉动流速规律，出流工况，其脉动流速很大，流速脉动值可达到时均值的1.8倍，有别于脉动值较小的一般规律；进流工况，其脉动流速较小，符合脉动值绕时均值上下波动的一般规律。研究成果将为优化进出水口体型参数和分析引起拦污栅振动破坏提供理论依据。

Research on velocity distribution and fluctuation law of bidirectional flow structure of inlet/outlet

The side inlet/outlet of pumped storage power station channel system has complicated flow due to internal partial flow barriers,etc.,and its internal two-way flow law is not clear. In this paper,a typical inlet/outlet test device is established on the basis of an actual engineering inlet/outlet, and the advanced velocity measuring instrument is used for fine test research. Based on the measurement results of the Particle image velocimetry technology (PIV),it reveals the two-way flow rules. Under outflow conditions,the main flow is formed in the diffusion section of the middle hole and is located in the middle of the orifice,a low-velocity area is formed at the top of the diffusion section and the adjustment section, and the main flow in the side hole is not obvious. Under the inflow condition,there is a low-velocity area at the top of the middle hole and the side hole adjustment section,and the velocity distribution tends to be uniform after the water flows into the diffusion section. Based on the measurement results of Acoustic Doppler Velocimetry (ADV),it reveals the law of fluctuating velocity on the section of the trash rack. The fluctuating velocity of outflow conditions is very large,and can reach 1.8 times of the time-averaged value, which is different from the general rule of smaller pulsations. Under the inflow condition,the fluctuating velocity is very small,which conforms to the general law that the fluctuating velocity fluctuates around the time-averaged value. The research results will provide a theoretical basis for optimizing the parameters of the inlet/outlet shape and analyzing the vibration damage of the trash rack.