摘要
A modified polynomial preserving gradient recovery technique is proposed. Unlike the polynomial preserving gradient recovery technique,the gradient recovered with the modified polynomial preserving recovery(MPPR) is constructed element-wise, and it is discontinuous across the interior edges.One advantage of the MPPR technique is that the implementation is easier when adaptive meshes are involved.Superconvergence results of the gradient recovered with MPPR are proved for finite element methods for elliptic boundary problems and eigenvalue problems under adaptive meshes. The MPPR is applied to adaptive finite element methods to construct asymptotic exact a posteriori error estimates.Numerical tests are provided to examine the theoretical results and the effectiveness of the adaptive finite element algorithms.
A modified polynomial preserving gradient recovery technique is proposed. Unlike the polynomial preserving gradient recovery technique, the gradient recovered with the modified polynomial preserving recovery （MPPR） is constructed element-wise, and it is discontinuous across the interior edges. One advantage of the MPPR technique is that the implementation is easier when adaptive meshes are involved. Superconvergence results of the gradient recovered with MPPR are proved for finite element methods for elliptic boundary problems and eigenvalue problems under adaptive meshes. The MPPR is applied to adaptive finite element methods to construct asymptotic exact a posteriori error estimates. Numerical tests are provided to examine the theoretical results and the effectiveness of the adaptive finite element algorithms.
基金
supported by the national basic research program of China under grant 2005CB321701
the program for the new century outstanding talents in universities of China.
