Abstract: Based on lattice Boltzmann method, a walldriven incompressible viscous flow was simulated in a semi-circular cavity. The treatment for curved boundary with second accurate was used to obtain the streamlinesand vorticity contours and the velocity component along the center line of semi-circular cavity of the steady states for different Reynolds numbers. When Reynolds number is small, the final steady state flow consistsof one vortex only. As Reynolds number increases, a secondary vortex arises. The size of the vortices is associated with Reynolds numbers too. The numerical results show that lattice Boltzmann method is simple, effective, and suitable to handling the case.

Key words: lattice Boltzmann method, semicircular cavity flow, curved boundary