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Numerische Mathematik

, Volume 58, Issue 1, pp 287–298 | Cite as

Superconvergence for rectangular mixed finite elements

  • Ricardo Durán
Article

Summary

In this paper we prove superconvergence error estimates for the vector variable for mixed finite element approximations of second order elliptic problems. For the rectangular finite elements of Raviart and Thomas [19] and for those of Brezzi et al. [4] we prove that the distance inL2 between the approximate solution and a projection of the exact one is of higher order than the error itself.

This result is exploited to obtain superconvergence at Gaussian points and to construct higher order approximations by a local postprocessing.

Subject classifications

AMS(MOS): 65N30 CR:G1.8 

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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Ricardo Durán
    • 1
  1. 1.Departamento de MatemáticaUniversidad Nacional de La PlataLa PlataArgentina

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