Extended Lattice Boltzmann Equation for Simulation of Flows around Bluff Bodies in High Reynolds Number
نویسندگان
چکیده
The Lattice Boltzmann method, a molecule kinetic-based approach, is presented to solve fluid dynamics. Based on the theory of turbulence and molecule kinetics, an extended Lattice Boltzmann equation is put forward to solve turbulent flow with high Reynolds number, in which sub-grid turbulence model is used to simulate vortex viscosity as well as turbulence relaxation time is introduced to modify the normal LBGK equation. The method to evaluate the turbulence relaxation time with particle distribution function is proposed combining with Smagorinsky turbulence model. Further more, the extended Lattice Boltzmann method is applied to simulate the flows around square cylinder in the range of Reynolds number from 10 to 100,000 and circular cylinder with Reynolds numbers from 10 to 140,000.
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