A Comparison of Two Boundary Conditions for the Fluid Flow Simulation in a Stirred Tank

Three dimensional turbulent flow in a stirred tank with moving blades has been numerically studied. For the numerical simulation, a 3D parallel flow solver has been developed based on the lattice Boltzmann method. The large eddy simulation method has been used for the turbulence modeling. To improve the accuracy of the flow simulation in stirred tanks, a commonly used boundary condition for moving walls as well as a proposed alternative boundary condition have been investigated in great details. The present investigations show that the proposed improved bounce back method generates accurate results compared with those obtained using commonly used force field method. However, the implementation of the proposed boundary condition is more difficult for cases with complex moving walls.