Numerical Simulation of Cavitating Turbulent Flow in a Francis Turbine with Draft Tube Natural Air Admission

Abstract:

The paper presents numerical analysis of cavitating turbulent flow in a high head Francis turbine with draft tube natural air admission at part load operation. Analysis was performed by OpenFOAM code. A mixture assumption and a finite rate mass transfer model were introduced. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. The pressure distribution and the flow of air in the draft tube are analyzed in detail. Simulation results show that the pressure fluctuations on the draft tube wall can reduce with natural air admission.

• Periodical: Applied Mechanics and Materials (Volumes 291-294)
• Pages: 1963-1968
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.291-294.1963
• Online since: February 2013
• Authors: Hong Ming Zhang, Li Xiang Zhang
• Keywords: Air Admission, Cavitating Turbulent Flow, Computational Fluid Dynamics (CFD), Francis Turbine, OpenFOAM

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