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Int. J. Numer. Anal. Mod., 3 (2006), pp. 273-282. |
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Superconvergence of tetrahedral linear finite element Long Chen 1 1 Department of Mathematics, The Pennsylvania State University, University Park, PA, 16802, USAReceived by the editors July 1, 2004 and, in revised form, October 22, 2004 Abstract In this paper, we show that the piecewise linear finite element Solution U-h and the linear interpolation u(I) have superclose gradient for tetrahedral meshes, where most elements are obtained by dividing approximate parallelepiped into six tetrahedra. We then analyze a post-processing gradient recovery scheme, showing that the global L-2 projection of del u(h) is a superconvergent gradient approximation to del(u). AMS subject classifications: 65N30 Key words: superconvergence; finite element methods; tetrahedral elements; post-processing Email: long c@math.psu.edu |