Francis turbine draft tube modelling for prediction of pressure fluctuations on prototype

9th International Symposium on Cavitation

Alligné, S.^1 ; Landry, C.^2 ; Favrel, A.^2 ; Nicolet, C.^1 ; Avellan, F.^2

Powervision Engineering Sàrl, Chemin des champs courbes 1, Ecublens

1024, Switzerland^1

EPFL Laboratory for Hydraulic Machines, Avenue de Cour 33 bis, Lausanne

1007, Switzerland^2

关键词: Cavitation flow;    Eigen modes;    Equipment industries;    Forced response;    Generating unit;    Pressure fluctuation;    Reduced scale models;    Reliable operation;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/656/1/012056/pdf
DOI  :  10.1088/1742-6596/656/1/012056

来源: IOP

【 摘 要 】

The prediction of pressure fluctuations amplitudes on Francis turbine prototype is a challenge for hydro-equipment industry since it is subjected to guarantees to ensure smooth and reliable operation of the hydro units. The European FP7 research project Hyperbole aims to setup a methodology to transpose the pressure fluctuations measured on the reduced scale model to the prototype generating units. This paper presents this methodology which relies on an advanced modelling of the draft tube cavitation flow, and focuses on the transposition to the prototype of the draft tube model parameters identified on the reduced scale model. Different modelling assumptions of the draft tube are considered and their influence on the eigenmodes and the forced response of the system are presented.