MASS BALANCE IN LATTICE BOLTZMANN METHOD WITH DIRICHLET VELOCITY BOUNDARY CONDITION

Many different methods can be used to treat open boundary conditions in the lattice Boltzmann method. The Zou-He method, finite difference velocity gradient method, and regularized method are reviewed and compared for the Dirichlet velocity condition for Poiseuille flow with different Reynolds numbers. Using the same convergence criterion, all the numerical procedures are carried on until steady states are reached. The obtained velocities and pressures are checked and compared with analytical solutions and mass balances for different methods. The results indicate that all the numerical data agreed well with the analytical solutions and the Zou-He method results satisfy the mass balance better than the others.