Hydraulic Performance Experiment and Numerical Simulation of Hydraulic Turbine at Different Speeds
In order to reveal the hydraulic performance of hydraulic turbines at different speeds,a centrifugal pump as turbine(PAT)with a specific speed of 48 was taken as the research object.The variation of the speed of the hydraulic turbine with the flow rate and head under different loads was studied by experiments.The RNG κ-ε turbulence model was used for numerical calculation at different speeds.Then the hydraulic performance and internal flow characteristics of the hydraulic turbine under various working conditions were analyzed.The results show that with the increase of the rotation-al speed,the high efficiency area of the turbine becomes wider,and the high efficiency point obviously shifts to the large flow.The inflow parameters(flow rate,pressure)have a certain influence on the rotational speed.The rotational speed changes linearly with the flow rate and changes with the head in a power function.The smaller the flow rate is,the worse the uniformity of pressure and velocity streamline distribution in the impeller are,and the lower the turbine efficiency is.At high speed,the flow in the impeller is relatively stable,which is consistent with the external characteristics of the tur-bine.This study has important reference significance for the efficient and stable operation of the low specific speed pump reverse hydraulic turbine.
万方数据
维普
