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Coupled Systems Mechanics Volume 7, Number 4, August 2018 , pages 421-440 DOI: https://doi.org/10.12989/csm.2018.7.4.421 |
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Simulation of turbulent flow of turbine passage with uniform rotating velocity of guide vane |
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Wen-Quan Wang and Yan Yan
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| Abstract | ||
| In this study, a computational method for wall shear stress combined with an implicit direct-forcing immersed boundary method is presented. Near the immersed boundaries, the sub-grid stress is determined by a wall model in which the wall shear stress is directly calculated from the Lagrangian force on the immersed boundary. A coupling mathematical model of the transition process for a model Francis turbine comprising turbulent flow and rotating rigid guide vanes is established. The spatiotemporal distributions of pressure, velocity, vorticity and turbulent quantity are gained with the transient process; the drag and lift coefficients as well as other forces (moments) are also obtained as functions of the attack angle. At the same time, analysis is conducted of the characteristics of pressure pulsation, velocity stripes and vortex structure at some key parts of flowing passage. The coupling relations among the turbulent flow, the dynamical force (moment) response of blade and the rotating of guide vane are also obtained. | ||
| Key Words | ||
| immersed boundary method; velocity correction; large eddy simulation; turbulent flow; transition process; hydraulic turbine | ||
| Address | ||
| Wen-Quan Wang and Yan Yan: Department of Engineering Mechanics, Kunming University of Science and Technology, Kunming 650500, China | ||
