Phase resolved velocity measurements at the draft tube cone of the turbine-99 test case

The Turbine-99 test case, a Kaplan draft tube, has been studied extensively both experimentally and numerically. To further complete the experimental data of this test case, phase resolved velocity profiles in the draft tube cone are presented in this paper. The phase resolved velocity profiles have been measured with a 2-component LDA equipment measuring both the tangential and the axial velocity components of the flow. The measurements were synchronised with a pulse from the runner shaft that gives the angular position/phase of each velocity measurement. The result shows a clear impact of the runner blade wakes on the flow distribution in the draft tube cone. Further down in the cone the blade wakes are still visible, even if noticeable weaker, and they have increased their extent in the tangential direction.Godkänd; 2008; Bibliografisk uppgift: 1 CD-ROM; 20081111 (ysko)