Author(s)

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

Abstract

This paper presents the results of simulations of the three-dimensional flow through the Francis turbine runner of the Derbendikan power station. A three-dimensional model of the whole Francis turbine runner was prepared according to specifications provided and then the investigated flow model (fluid domain) extracted from the structured model (Francis turbine runner model). Pressure distribution and water velocity have been analysed. The results form input data for the mechanical analysis in the second part. The results show that the maximum absolute pressure is reached (5.387x105 Pa) at the leading edge of the turbine runner. Keywords: Francis turbine runner, CFD modelling. 1 Introduction The flow in hydraulic turbines of the Francis type is quite complicated due to its three-dimensional nature and the curvature of the passages between runner blades. The complexity of the problem requires the application of numerical approaches that are capable of producing accurate results for pressure distributions on the runner and flow velocity. The application of CFD is an efficient way for analysis fluid flow through hydraulic turbines [1, 2, 11]. Nava et al. [3] presented an application of CFD to compute the loads caused by water pressure on a blade of the Francis turbine runner. An experimental approach has been successfully used [4–6] to measure the pressure on the blade, where pressure transducers are embedded in the model runner blades without geometrical alteration. There is a good agreement between numerical simulation and experimental measurements as confirmed by [1, 7], who compared the

Keywords

Francis turbine runner, CFD modelling.