Author(s)

R. A. Saeed, V. Popov & A. N. Galybin

Abstract

This paper presents the results of simulations of the complete three-dimensional fluid flow through the Spiral Casing, Stay Vane, Guide Vane, and then through the Francis turbine runner of the Derbendikan power station. To investigate the flow in the Francis turbine and also to identify the loads acting on the turbine blades, a three-dimensional model was prepared according to specifications provided. The results show that the maximum absolute pressure of 4.4x105 Pa is reached at the leading edge of the turbine runner and the maximum tangential velocity reaches 33 m/s in the turbine runner. Keywords: Francis turbine runner, numerical simulation, CFD modelling. 1 Introduction Generally the flow field in Francis turbines is quite complicated due to its threedimensional nature and the curvature of the passages between runner blades. The complexity of the problem requires the application of numerical approaches which are capable of producing accurate results for flow velocity field and pressure distributions on the runner. The application of CFD is an efficient way for the analysis of fluid flow through hydraulic turbines [1]. Nava et al. [2] presented an application of CFD to compute the loads caused by water pressure on a blade of the Francis turbine runner. There is a satisfactory agreement between numerical simulations and experimental measurements as reported by Farhat et al. [4], who compared the flow simulation results and experimental data for the whole Francis turbine. Three-dimensional steady flow analysis of the flow passages from the entrance runner to the outlet in Francis turbine type has

Keywords

Francis turbine runner, numerical simulation, CFD modelling.