Shape Function Modification for the Imposition of EFGM Essential Boundary Conditions

Title & Authors
Shape Function Modification for the Imposition of EFGM Essential Boundary Conditions
Seok, Byeong-Ho; Song, Tae-Han; Im, Jang-Geun;

Abstract
For the effective analysis of an engineering problem, meshless methods which require only positioning finite points without the element meshing recently have been proposed and being studied extensively. Meshless methods have difficulty in imposing essential boundary conditions directly, because non-interpolate shape functions originated from an approximation process are used. So some techniques, which are Lagrange multiplier method, modified variational principles and coupling with finite elements and so on, were introduced in order to impose essential boundary conditions. In spite of these methods, imposition of essential boundary conditions have still many problems like as non-positive definiteness, inaccuracy and negation of meshless characteristics. In this paper, we propose a new method which modifies shape function. Through numerical tests, convergence, accuracy and validity of this method are compared with the standard EFGM which uses Lagrange multiplier method or modified variational principles. According to this study, the proposed method shows the comparable accuracy and efficiency.
Keywords
Element Free Galerkin Method(EFGM);Meshless Method;Essential Boundary Conditions;Interpolation Characteristics;Shape Function;
Language
Korean
Cited by
1.
무요소법에서 절점 적분의 개선방안,임장근;송태한;석병호;

대한기계학회논문집A, 2001. vol.25. 9, pp.1376-1383
2.
버블패킹기법을 이용한 무요소 갤러킨법에 관한 연구,정순완;최유진;김승조;

대한기계학회논문집A, 2000. vol.24. 10, pp.2469-2476
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