A Two-Level Finite Element Method for the Stationary Navier-Stokes Equations Based on a Stabilized Local Projection

In this article, we propose a two-level finite element method to analyze the approximate solutions of the stationary Navier-Stokes equations based on a stabilized local projection. The local projection allows to circumvent the Babuska-Brezzi condition by using equal-order finite element pairs. The local projection can be used to stabilize high equal-order finite element pairs. The proposed method combines the local projection stabilization method and the two-level method under the assumption of the uniqueness condition. The two-level method consists of solving a nonlinear equation on the coarse mesh and solving a linear equation on fine mesh. The nonlinear equation is solved by the one-step Newtonian iteration method. In the rest of this article, we show the error analysis of the lowest equal-order finite element pair and provide convergence rate of approximate solutions. Furthermore, the numerical illustrations coincide with the theoretical analysis expectations. From the view of computational time, the results show that the two-level method is effective to solve the stationary Navier-Stokes equations. (C) 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 460-477, 2011