Abstract:To realize the numerical simulation of the formation and evolution process of the free surface vortex in high Reynolds number flow issues, the standard Smagorinsky subgrid stress model was introduced into the three dimensional of single phase free surface lattice Boltzmann method, and the LES-LBM was established. Considered that the inlet Reynolds number were 5×104 and 105,the Formation and evolution process of the free surface vortex upon suction inlet of rectangular water tank under the effect of gravity and Coriolis force was simulated by LES-LBM. The main flow features of the free surface vortex were represented in the process. According to the flow characteristics, the developing process was divided into four typical stages. By comparing the high Reynolds number flow problems with and without Coriolis force, the action of it was tested. The regularities of the radial velocity, tangential velocity and axial velocity of the B-type(Dye core & Trash pulling core) and D-type(Full air core) free surface vortex along the direction of radial were mainly analyzed. The numerical simulation results show that the formation and evolution process of free surface vortex in high Reynolds number can be effectively simulated by LES-LBM. The effect of Coriolis force which promotes the free surface vortex production and development has been proved. The regularities of the velocity components of free surface vortex are qualitatively consistent with the experimental results and they barely change along with the variation of the inlet Reynolds number.
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