Trefftz functions for non-stationary problems

• Autorzy: Grysa K. , Maciejewska B.

Warianty tytułu

PL

Funkcje Trefftza dla problemów niestacjonarnych

• Języki publikacji: EN

Abstrakty

EN

Different types of Trefftz functions for non-stationary linear and weakly nonlinear differentia equations are presented. The Trefftz methods are defined and briefly described. Certain results for non-stationary problems of heat conduction (among others boundary temperature identification and thermal diffusivity estimation), for beam vibration, for thermoelasticity and for the wave equation (direct and inverse problem of membrane vibrations) are shown. In many cases, the FEM with Trefftz functions (FEMT) as probe functions is applied. Three kinds of FEMT are tested for direct and inverse non-stationary problems. Examples of the making use of T-functions for solving inverse problems and smoothing inaccurate input data are discussed.

PL

W pracy przedstawione są rożne rodzaje funkcji Trefftza dla niestacjonarnych liniowych i słabo nieliniowych równań różniczkowych. Zdefiniowane są i krotko opisane metody Trefftza. Prezentowane są niektóre wyniki dla niestacjonarnych problemów przewodzenia ciepła (m.in. identyfikacja temperatury na brzegu oraz estymacja dyfuzyjności termicznej), drgań belki oraz dla termosprężystości i równania falowego (prosty i odwrotny problem drgań membrany). W pracy pokazany jest również przykład zastosowania metody elementów skończonych z funkcjami Trefftza (MEST) jako funkcjami próbnymi. Trzy rodzaje MEST są testowane na prostych i odwrotnych problemach niestacjonarnych. W pracy omawiane są również przykłady zastosowania T-funkcji w rozwiązywaniu problemów odwrotnych w połączeniu z wygładzaniem niedokładnych danych wejściowych.

Słowa kluczowe

EN

non-stationary inverse problems; Trefftz method; FEMT

• Wydawca: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
• Czasopismo: Journal of Theoretical and Applied Mechanics
• Rocznik: 2013
• Tom: Vol. 51 nr 2
• Strony: 251--264
• Opis fizyczny: Bibliogr. 36 poz., tab.

Twórcy

autor

Grysa K.

• Kielce University of Technology, Department of Management and Computer Modeling, Kielce, Poland

autor

Maciejewska B.

• Kielce University of Technology, Department of Management and Computer Modeling, Kielce, Poland

Bibliografia

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