摘要

Based on two-grid discretizations, a two-parameter stabilized finite element method for the steady incompressible Navier-Stokes equations at high Reynolds numbers is presented and studied. In this method, a stabilized Navier-Stokes problem is first solved on a coarse grid, and then a correction is calculated on a fine grid by solving a stabilized linear problem. The stabilization term for the nonlinear Navier-Stokes equations on the coarse grid is based on an elliptic projection, which projects higher-order finite element interpolants of the velocity into a lower-order finite element interpolation space. For the linear problem on the fine grid, either the same stabilization approach (with a different stabilization parameter) as that for the coarse grid problem or a completely different stabilization approach could be employed. Error bounds for the discrete solutions are estimated. Algorithmic parameter scalings of the method are also derived. The theoretical results show that, with suitable scalings of the algorithmic parameters, this method can yield an optimal convergence rate. Numerical results are provided to verify the theoretical predictions and demonstrate the effectiveness of the proposed method.