Preliminary Measurements of the Radial Velocity in the Francis-99 Draft Tube Cone

Francis-99 Workshop 1: steady operation of Francis turbines

Bergan, Carl^1 ; Amiri, Kaveh^2 ; Cervantes, Michel J.^1,2 ; Dahlhaug, Ole G.^1

Department of Energy and Process Engineering, Waterpower Laboratory, Norwegian University of Science and Technology, Trondheim, Norway^1

Department of Engineering Science and Mathematics, Luleå University of Technology, Luleå, Sweden^2

关键词: Gyroscopic Effects;    Laser Doppler Velocimetry;    Measurements of;    Operating points;    Radial velocity;    Radial velocity datum;    Two-dimensional particle image velocimetry;    Velocity profiles;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/579/1/012014/pdf
DOI  :  10.1088/1742-6596/579/1/012014

来源: IOP

【 摘 要 】

Two-dimensional particle image velocimetry (PIV) measurements in the draft tube cone of the Francis-99 model have been performed to complete the actual experimental data set with radial velocity data. The velocity profiles obtained presented some variation, which reason has not yet been identified. The presented results are therefore presented as preliminary until the reason is assessed. The axial velocity profiles corroborate well with the ones previously measured with laser Doppler velocimetry (LDV) for all operating points investigated. The radial velocity measured is small in magnitude for all operating points compared to the axial velocity. A gyroscopic effect induced by the swirl leaving the runner and the draft tube bend seems to induce an asymmetry in the draft tube cone.