The Study On Water Flow Optimization And Improvement Of Intake Of Dongping Hydropower Station

The influence factors of the flow regime are complicated,such as the different ways of hydropower station hub layout,operation conditions and something else,would bring many effects to the water diversion,discharge,shipping and so on.The existence of vortex has the serious influence on the water flow.It could lower the flow ability,even cause the vibration of hydraulic structures and damage units.It would directly affect the power output and the full use of water.Therefore,it is of great significance to study the water flow characteristics of the inlet of the power station and optimize the water flow conditions at the inlet of the power station to ensure the safe operation of the power station and the utilization of water energy.This paper takes the Dongping hydropower plant as the engineering background,and uses the combination of model test and numerical simulation to study the flow characteristics at the inlet of the power station.Analyze the effects of flow and complex terrain boundaries on the inlet flow pattern,and explore the engineering measures for improving the flow regime at the inlet of Dongping Hydropower Station.The main research contents and results are as follows:(1)Use the three-dimensional k-s turbulence model and the VOF method to simulate the current status of power intake ijilets and the water flow patterns at inlets under different scenarios.Comparisons are made between inlet flow conditions and flow velocity distributions under different operating conditions.Analyze the causes of poor flow conditions such as vortices and lateral flow generated by power plants.(2)Based on relevant data and numerical simulation results,a physical model was established with a model scale of 1:45 to perform current state simulation inversion of the entire power plant,and 18 groups of test plans were formulated for changes in boundary conditions such as guide walls and sand barriers.Analyze the effects of flow and complex terrain boundaries on the inlet flow pattern,and optimize the engineering program through physical model tests.(3)Intergrate the results of numerical simulation and physical model research,linear transform the gate piers between 3#and 4#units in the optimized scheme.Analyze the flow patterns,lateral flow sizes,front vortex types,and distribution states of the turbines in the study area during operation of each unit.Comprehensively analyze the results of each test,propose a flow state improvement recommendation program,and make suggestions for the scheduling operation mode.