CFD Simulation Analysis Of The Whole Flow Channel Of Francis Turbine

There are many studies on the internal flow field and pressure pulsation characteristics of the vertical Francis turbines,but there are few studies on the internal flow conditions of the horizontal Francis turbine and its pressure pulsation characteristics of the draft tube.The internal flow characteristics and the main factors of its stable operation can be further deepened.This paper firstly summarizes the domestic and international research status of hydraulic turbine whole flow passage simulation based on CFD technology,and then uses Fluent software to calculate the three-dimensional turbulent flow of the whole flow passage of a horizontal Francis turbine under three typical operating points.The main work and results are as follows:1.Based on the actual geometrical parameters of the turbine's four components,then UGS NX 6.0 software is used to establish a three-dimensional geometric model of the entire fluid calculation domain from the spiral case inlet to the draft tube outlet.2.Overview of the grid and its generation methods,and then use the ICEM CFD 14.5 software to generate the computational domain's meshes.3.The basic application and calculation method of numerical simulation in hydraulic turbine are introduced.Then,using the Fluent 14.5 software,and selecting the Realizable k-? turbulence model to calculate.The governing equations are discretized using the first-order upwind style,and the flow field calculation method uses the SIMPLE algorithm.Four monitoring points at the draft tube are set under three typical operating conditions and three-dimensional turbulent numerical calculations are performed for the whole flow passage of the entire turbine.4.The results of the numerical calculation are processed by Tecplot 360 EX 2015 R1 software,which will generate the streamline diagram,pressure distribution chart,etc.of each component under three typical operating conditions.And then this paper tries to analyze the performance of the turbine,to explore the internal flow of it and to find the tailrace vortex rope and pressure pulsation characteristics.In this paper,numerical simulation method is used.By comparing and analyzing the inside flow characteristics of the whole flow passage of the entire turbine under three typical operating points,it provides a reference for further optimization design and stable operation of the horizontal Francis turbine.