Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen
OPUS4-3422 Konferenzveröffentlichung Nguyen-Thanh, Nhon; Nguyen-Xuan, Hung; Bordas, Stéphane Pierre Alain; Rabczuk, Timon Isogeometric finite element analysis using polynomial splines over hierarchical T-meshes Isogeometric finite element analysis has become a powerful alternative to standard finite elements due to their flexibility in handling complex geometries. One major drawback of NURBS based isogeometric finite elements is their less effectiveness of local refinement. In this study, we present an alternative to NURBS based isogeometric finite elements that allow for local refinement. The idea is based on polynomial splines and exploits the flexibility of T-meshes for local refinement. The shape functions satisfy important properties such as non-negativity, local support and partition of unity. We will demonstrate the efficiency of the proposed method by two numerical examples. 10.1088/1757-899X/10/1/012238 Institut für Strukturmechanik
OPUS4-3407 Wissenschaftlicher Artikel Nguyen-Thanh, Nhon; Rabczuk, Timon; Nguyen-Xuan, Hung; Bordas, Stéphane Pierre Alain An alternative alpha finite element method (A?FEM) free and forced vibration analysis of solids using triangular meshes An alternative alpha finite element method (A?FEM) free and forced vibration analysis of solids using triangular meshes 23 Journal of Computational and Applied Mathematics 2112 2135 Institut für Strukturmechanik
OPUS4-3401 Wissenschaftlicher Artikel Nguyen-Xuan, Hung; Rabczuk, Timon; Nguyen-Thanh, Nhon; Nguyen-Thoi, T.; Bordas, Stéphane Pierre Alain A node-based smoothed finite element method (NS-FEM) for analysis of Reissner-Mindlin plates A node-based smoothed finite element method (NS-FEM) for analysis of Reissner-Mindlin plates 22 Computational Mechanics 679 701 Institut für Strukturmechanik
OPUS4-3396 Wissenschaftlicher Artikel Nguyen-Thanh, Nhon; Rabczuk, Timon; Nguyen-Xuan, Hung; Bordas, Stéphane Pierre Alain An alternative alpha finite element method with stabilized discrete shear gap technique for analysis of Mindlin-Reissner plates An alternative alpha finite element method with stabilized discrete shear gap technique for analysis of Mindlin-Reissner plates 16 Finite Elements in Analysis & Design 519 535 Institut für Strukturmechanik
OPUS4-3395 Wissenschaftlicher Artikel Nguyen-Thanh, Nhon; Nguyen-Xuan, Hung; Bordas, Stéphane Pierre Alain; Rabczuk, Timon Isogeometric analysis using polynomial splines over hierarchical T-meshes for two-dimensional elastic solids Isogeometric analysis using polynomial splines over hierarchical T-meshes for two-dimensional elastic solids 16 Computer Methods in Applied Mechanics and Engineering 1892 1908 Institut für Strukturmechanik
OPUS4-3393 Wissenschaftlicher Artikel Simpson, R.; Bordas, Stéphane Pierre Alain; Trevelyan, J.; Kerfriden, Pierre; Rabczuk, Timon An Isogeometric Boundary Element Method for elastostatic analysis The concept of isogeometric analysis, where functions that are used to describe geometry in CAD software are used to approximate the unknown fields in numerical simulations, has received great attention in recent years. The method has the potential to have profound impact on engineering design, since the task of meshing, which in some cases can add significant overhead, has been circumvented. Much of the research effort has been focused on finite element implementations of the isogeometric concept, but at present, little has been seen on the application to the Boundary Element Method. The current paper proposes an Isogeometric Boundary Element Method (BEM), which we term IGABEM, applied to two-dimensional elastostatic problems using Non-Uniform Rational B-Splines (NURBS). We find it is a natural fit with the isogeometric concept since both the NURBS approximation and BEM deal with quantities entirely on the boundary. The method is verified against analytical solutions where it is seen that superior accuracies are achieved over a conventional quadratic isoparametric BEM implementation. Computer Methods in Applied Mechanics and Engineering 10.1016/j.cma.2011.08.008 Institut für Strukturmechanik
OPUS4-3390 Wissenschaftlicher Artikel Chen, Lei; Rabczuk, Timon; Liu, G.R.; Zeng, K.Y.; Kerfriden, Pierre; Bordas, Stéphane Pierre Alain Extended finite element method with edge-based strain smoothing (ESm-XFEM) for linear elastic crack growth This paper presents a strain smoothing procedure for the extended finite element method (XFEM). The resulting "edge-based" smoothed extended finite element method (ESm-XFEM) is tailored to linear elastic fracture mechanics and, in this context, to outperform the standard XFEM. In the XFEM, the displacement-based approximation is enriched by the Heaviside and asymptotic crack tip functions using the framework of partition of unity. This eliminates the need for the mesh alignment with the crack and re-meshing, as the crack evolves. Edge-based smoothing (ES) relies on a generalized smoothing operation over smoothing domains associated with edges of simplex meshes, and produces a softening effect leading to a close-to-exact stiffness, "super-convergence" and "ultra-accurate" solutions. The present method takes advantage of both the ES-FEM and the XFEM. Thanks to the use of strain smoothing, the subdivision of elements intersected by discontinuities and of integrating the (singular) derivatives of the approximation functions is suppressed via transforming interior integration into boundary integration. Numerical examples show that the proposed method improves significantly the accuracy of stress intensity factors and achieves a near optimal convergence rate in the energy norm even without geometrical enrichment or blending correction. Computer Methods in Applied Mechanics and Engineering 10.1016/j.cma.2011.08.013 Institut für Strukturmechanik
OPUS4-3384 Wissenschaftlicher Artikel Nguyen-Vinh, H.; Bakar, I.; Msekh, Mohammed Abdulrazzak; Song, Jeong-Hoon; Muthu, Jacob; Zi, Goangseup; Le, P.; Bordas, Stéphane Pierre Alain; Simpson, R.; Natarajan, S.; Lahmer, Tom; Rabczuk, Timon Extended Finite Element Method for Dynamic Fracture of Piezo-Electric Materials We present an extended finite element formulation for dynamic fracture of piezo-electric materials. The method is developed in the context of linear elastic fracture mechanics. It is applied to mode I and mixed mode-fracture for quasi-steady cracks. An implicit time integration scheme is exploited. The results are compared to results obtained with the boundary element method and show excellent agreement. 12 Engineering Fracture Mechanics 19 31 10.1016/j.engfracmech.2012.04.025 Institut für Strukturmechanik
OPUS4-3383 Wissenschaftlicher Artikel Natarajan, S.; Chakraborty, S.; Thangavel, M.; Bordas, Stéphane Pierre Alain; Rabczuk, Timon Size dependent free flexural vibration behavior of functionally graded nanoplates Size dependent free flexural vibration behavior of functionally graded nanoplates 6 Computational Materials Science 74 80 Institut für Strukturmechanik
OPUS4-3378 Wissenschaftlicher Artikel Nguyen-Xuan, Hung; Liu, G.R.; Bordas, Stéphane Pierre Alain; Natarajan, S.; Rabczuk, Timon An adaptive singular ES-FEM for mechanics problems with singular field of arbitrary order An adaptive singular ES-FEM for mechanics problems with singular field of arbitrary order 21 Computer Methods in Applied Mechanics and Engineering 252 273 Institut für Strukturmechanik