Abstract
The hydrodynamic properties of free surface vortices at hydraulic intakes were investigated. Based on the axisymmetric Navier–Stokes equations and empirical assumptions, two sets of formulations for the velocity distributions and the free surface profiles are proposed and validated against measurements available in the literature. Compared with previous formulae, the modifications based on Mih's formula are found to greatly improve the agreement with the experimental data. Physical model tests were also conducted to study the intake vortex of the Xiluodu hydroelectric project in China. The proposed velocity distribution formula was applied to the solid boundary as considered by the method of images. A good agreement was again observed between the prediction and the measurements.
Acknowledgements
This research was supported by the National Key Basic Research Project of China (2006CB403304), State Key Laboratory of Hydroscience and Engineering, Tsinghua University (2010-TC-2, 2008-ZY-5, 2009-TC-2) and the Tsinghua University Initiative Scientific Research Program (2009THZ07060).