General aspects of Trefftz method and relations to error estimation of finite element approximations

  • Stephan Ohnimus University of Hannover
  • Marcus Rüter University of Hannover
  • Erwin Stein University of Hannover

Abstract

In this paper a guaranteed upper bound of the global discretization error in linear elastic finite element approximations is presented, based on a generalized Trefftz functional. Therefore, the general concept of complementary energy functionals and the corresponding approximation methods of Ritz, Trefftz, the method of orthogonal projection and the hypercircle method are briefly outlined. Furthermore, it is shown how to use a generalized Trefftz functional to solve a Neumann problem in linear elasticity. Based on an implicit a posteriori error estimator within the finite element method, using equilibrated local Neumann problems, the generalized Trefftz functional yields a computable guaranteed upper bound of the discretization error without multiplicative constants.

Keywords

References

[1] M. Ainsworth, J.T. Oden. A unified approach to a posteriori error estimation based on element residual methods. Numer. Math. , 65: 23- 50, 1993.
[2] M. Ainsworth, J.T. Oden. A posteriori error estimation in finite element analysis. Comput. Methods Appl. Mech. Engrg., 142: 1- 88, 1997.
[3] A.M. Arthurs. Complementary Variational Principles. Clarendon Press, Oxford, 1970.
[4] R.E. Bank, A. Weiser. Some a posteriori error estimators for elliptic partial differential equations. Math. Comp., 44(170): 283- 301, 1985.
[5] M.Sh. Birman. Variational methods of solution of boundary problems analogous to the method of Trefftz (in Russian) . Vestnik Leningrad. Univ. / Serija Matematiki, Mechaniki i Astronomii, 13: 69- 89, 1956.
Published
Mar 2, 2023
How to Cite
OHNIMUS, Stephan; RÜTER, Marcus; STEIN, Erwin. General aspects of Trefftz method and relations to error estimation of finite element approximations. Computer Assisted Methods in Engineering and Science, [S.l.], v. 8, n. 2-3, p. 425-437, mar. 2023. ISSN 2956-5839. Available at: <https://cames.ippt.pan.pl/index.php/cames/article/view/1180>. Date accessed: 14 nov. 2024.
Section
Articles