hello,
I am using finite difference lattice boltzmann problem(FDLBM) to simulate lid driven flow,the mode is D2Q9 .the forward Euler difference is used to compute the time derivative and the central difference is used to compute the space derivative .boundary conditions use Non-equilibrium extrapolation method(GUO,etl).But the error doesn’t converge. I don’t konw why. so i want someone can help me point out the problem. thank you.