DOI QR코드

DOI QR Code

무요소법에서 가중함수를 수정한 필수경계조건 처리법

Treatment of Essential Boundary Conditions using Modified Weight Functions in Meshless Method

  • 강명석 (한국과학기술원 대학원 기계공학과) ;
  • 윤성기 (한국과학기술원기계공학과)
  • 발행 : 2000.11.01

초록

In meshless methods some techniques to impose essential boundary conditions have been developed since the approximations do not satisfy Kronecker delta properties at nodal points. In this study, new scheme for imposing essential boundary conditions is developed. Weight functions are modified by multiplying with auxiliary weight functions and the resulting shape functions satisfy Kronecker delta property on the bound ary nodes. In addition, the resulting shape functions possess and interpolation features on the boundary segments where essential boundary conditions are prescribed. Therefore the essential boundary conditions can be exactly satisfied with the new method. More importantly, the impositions of essential boundary conditions using the present method is relatively easy as in finite element method. Numerical examples show that the method also retains high convergence rate comparable to Lagrange multiplier method.

키워드

참고문헌

  1. Lancaster, P. and Salkauskas, 1981, K., 'Surfaces Generated by Moving Least Square Methods,' Mathematics of Computation, Vol. 37, No. 155, pp. 141-158 https://doi.org/10.2307/2007507
  2. Nayroles, B., Touzot, G., and Villon, P., 1992, 'Generalizing the Finite Element Method: Diffuse Approximation and Diffuse Elements,' Computational Mechanics, Vol. 10, pp. 307-318 https://doi.org/10.1007/BF00364252
  3. Belytschko, T., Lu, Y.Y., and Gu, L., 1994, 'Element-Free Galerkin Methods, International Journal for Numerical Methods in Engineering,' Vol. 37, pp. 229-256 https://doi.org/10.1002/nme.1620370205
  4. Lu, Y.Y., Belytschko, T., and Gu, L., 1994, 'A New Implementation of the Element Free Galerkin Method,' Computer Methods in Applied Mechanics and Engineering, Vol. 113, pp. 397-414 https://doi.org/10.1007/s004660050296
  5. Zhu, T., Atluri, S.N., 1998, 'A Modified Collocation Method and a Penalty Formulation for Enforcing the Essential Boundary Conditions in the Element Free Galerkin Method,' Computational Mechanics, Vol. 21, pp.211-222 https://doi.org/10.1016/S0045-7825(96)01083-3
  6. Chen, J.S., Pan, C., Wu, C.T., and Liu, W.K., 1996, 'Reproducing Kernel Particle Methods for Large Deformation Analysis of Non-linear Structures,' Computer Methods in Applied Mechanics and Engineering. Vol. 139, pp. 195-227 https://doi.org/10.1016/S0045-7825(98)00014-0
  7. G nther, F.C. and Liu, W.K., 1998, 'Implementation of Boundary Conditions for Meshless Methods,' Computer Methods in Applied Mechanics and Engineering, Vol. 163, pp. 205-230 https://doi.org/10.1016/0045-7825(94)90056-6
  8. Kaljevic, I., and Saigal, S., 1997, 'An Improved Element Free Galerkin Formulation,' International Journal for Numerical Methods in Engineering, Vol. 40, No. 16, pp. 2953-2974 https://doi.org/10.1002/(SICI)1097-0207(19970830)40:16<2953::AID-NME201>3.0.CO;2-S
  9. Chen J.-S., Wang H.-P. and Liu W.-K., 1999, 'Mesh free Method with Enhanced Boundary Condition Treatments for Metal Forming Simulation,' The 1999 NSF Design & Manufacturing Grantees Conference, Queen Mary, Long Beach, CA, USA, Jan. 5-8
  10. Krongauz, Y. and Belytschko, T., 1996, 'Enforcement of Essential Boundary Conditions in Meshless Approximations using Finite Elements,' Computer Methods in Applied Mechanics and Engineering, Vol. 131, pp. 133-145 https://doi.org/10.1016/0045-7825(95)00954-X
  11. Gosz, J. and Liu, W.K., 1996, 'Admissible Approximations for Essential Boundary Conditions in the Reproducing Kernel Particle Method,' Computational Mechanics, Vol. 19, pp. 120-135
  12. 석병호, 임장근, 1999, 'EFGM에서 필수경계조건을 위한 형상함수 수정법,' 대한기계학회 '99년도 춘계학술대회 논문집, pp. 838-842
  13. 석병호, 임장근, 1999, '특이커널함수를 사용한 RKPM,' 대한기계학회 '99 년도 추계학술 대회 논문집, pp. 578-583
  14. Timoshenko, S.P. and Goodier, J.N., 1970, Theory of Elasticity(Third Edition), McGraw Hill, New York