Numerical simulation of flow in a high head Francis turbine with prediction of efficiency, rotor stator interaction and vortex structures in the draft tube

Francis-99 Workshop 1: steady operation of Francis turbines

Jot, D.^1 ; Škerlavaj, A.^1 ; Morgut, M.^1 ; Menar, P.^1 ; Nobile, E.^2

Turbointitut, Ljubljana, Slovenia^1

University of Trieste, Department of Engineering and Architecture, Italy^2

关键词: Accurate prediction;    CFD (computational fluid dynamics);    Circumferential velocity;    Grid refinement;    Rotor-stator interactions;    Steady-state simulations;    Transient simulation;    Vortex structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/579/1/012006/pdf
DOI  :  10.1088/1742-6596/579/1/012006

来源: IOP

【 摘 要 】

The paper presents numerical simulations of flow in a model of a high head Francis turbine and comparison of results to the measurements. Numerical simulations were done by two CFD (Computational Fluid Dynamics) codes, Ansys CFX and OpenFOAM. Steady-state simulations were performed by k and SST model, while for transient simulations the SAS SST ZLES model was used. With proper grid refinement in distributor and runner and with taking into account losses in labyrinth seals very accurate prediction of torque on the shaft, head and efficiency was obtained. Calculated axial and circumferential velocity components on two planes in the draft tube matched well with experimental results.