A direct clock sparse solution of the mixed finite element equations

• Autorzy: Berković M. , Drašković Z. , Mijuca D.
• Konferencja: International Conference on Numerical Mathematics and Computational Mechanics (7 ; July 1996 ; Miskolc ; Węgry)
• Języki publikacji: EN

Abstrakty

EN

In this paper a practical procedure for the solution of really sized mixed problems, generating a continuous stress field (where appropriate) and having both the stress and displacement boundary conditions exactly satisfied, is described. The system matrix for the present formulation can be subdivided into the blocks, if the field variables (stresses and displacements) are separated for computational purposes. In addition, the structure of these blocks is sparse, similary as the structure of the stiffnes matrix in classical finite element analysis. Block sparse solution procedure, accounting for the pattern of the resulting system matrix is proposed. Computer implementation confirmed feasibility of the described solution procedure. In addition, numerical tests show remarkably high accuracy and convergence rate of the present mixed scheme for both the stresses and displacements. Due to high accuracy of the scheme, it can be competitive in comparaison with usual displacement approach, although the count of arethmetic operations for the same mesh density in mixed procedure can be order of magnitude larger than in classical finite element anaysis.

Słowa kluczowe

EN

finite element method

PL

metoda elementów skończonych

• Wydawca: Instytut Podstawowych Problemów Techniki PAN
• Czasopismo: Computer Assisted Mechanics and Engineering Sciences
• Rocznik: 1998
• Tom: Vol. 5, nr 1
• Strony: 21--30
• Opis fizyczny: Bibliogr. 12 poz., rys., wykr.

Twórcy

autor

Berković M.

• Faculty of Mathematics, P. O. Box, 11000 Belgrade, Yugoslavia

autor

Drašković Z.

• Faculty of Mathematics, P. O. Box, 11000 Belgrade, Yugoslavia

autor

Mijuca D.

• Faculty of Mathematics, P. O. Box, 11000 Belgrade, Yugoslavia

Bibliografia

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