Large eddy simulation of three-dimensional flow field based-on finite difference

Using the finite difference method and large eddy simulation(LES), a three-dimensional simulation of high temperature metal liquid in complex model is conducted. The N-S equation is split into advection step, diffusion step and propagation step with the time split-operator so that different physical processes can be treated by suitable schemes. Starting with split operator, all the difference methods used in the LES are inducted. The Four-Point Minimax Characteristics diference schemes(4PMC) is employed to simulate the advection term in present LES. Compare with QUICKTEST the accurate of the two class schemes are similar but the former spent less computational time than the latter The simulated results show that 4PMC succeeded in current LES. The diffusion and propagation steps are treated by the central difference method, the former being solved explicitly and the latter implicitly using the Gauss-Seidel iteration method. The near wall effect is considered by using a new two-layer model, a free-slip condition in wall boundary conditon instead of using a nomal no-slip condition which demands more fine grid. The result is in good agreemeng with the experiment, and the computational time is less than other results of LES.