Delfim Soares Jr.¹

CMES-Computer Modeling in Engineering & Sciences, Vol.76, No.1, pp. 61-82, 2011, DOI:10.3970/cmes.2011.076.061

Abstract This work proposes an iterative procedure to analyse pore-dynamic models discretized by time-domain Meshless Local Petrov-Galerkin formulations. By considering an iterative procedure based on a successive renew of variables, each phase of the coupled problem in focus can be treated separately, uncoupling the governing equations of the model. Thus, smaller and better conditioned systems of equations are obtained, rendering a more attractive methodology. A relaxation parameter is introduced here in order to improve the efficiency of the iterative procedure and an expression to compute optimal values for the relaxation parameter is discussed. Linear and nonlinear models are focused, highlighting that… More >

K. Lee¹, C.T. Wu², G.V. Clarke³, S.W. Lee⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.33, No.1, pp. 109-130, 2008, DOI:10.3970/cmes.2008.033.109

Abstract A geometrically nonlinear finite element analysis of a low areal density composite space reflector is conducted under static conditions and the results are compared with independently carried out experimental data. The finite element analysis is based on an assumed strain formulation of a geometrically nonlinear nine-node solid shell element. Numerical results are in good agreement with experimental data. This demonstrates the effectiveness of the present solid shell element approach when applied to the analysis of highly flexible space structures. The results of numerical analysis and the experimental data reported in the present paper provide a benchmark for future investigations on… More >

T.Y. Wu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.2, pp. 83-112, 2011, DOI:10.32604/cmes.2011.082.083

Abstract In this work nonlinear analysis of axi-symmetric solid using vector mechanics is performed, in which a triangular solid unit developed in compliance with the concept of vector form analysis is proposed. The vector form analysis uses point value description (rather than function) to describe motion and configuration of solid, which has governing equation directly formulated with respect to each mass point (particle). The point value description includes particles allocation for configuration and defining path elements for particle motion. In addition, constitutive conditions are properly defined to complete the formulation. The constitutive conditions linking the mass points in deformable solids are… More >

Jinling Long^1,2, Bingang Xu^1,3, Xiaoming Tao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.4, pp. 273-298, 2011, DOI:10.3970/cmes.2011.072.273

Abstract Moving slender threadline structures are widely used in various engineering fields. The dynamics of these systems is sometimes time dependent but in most cases follows a periodic pattern, and slender yarn motion in textile engineering is a typical problem of this category. In the present paper, we propose a nonlinear approach to model the dynamic behavior of slender threadline structures with a real example in the analysis of slender yarn motion in spinning. Moving boundary conditions of yarn are derived and a consequence of the perturbation analysis for the dimensionless governing equations provides the zero order approximate equation of motion… More >

Ali Kemal Baltacıoğlu¹, Ömer Civalek^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.68, No.1, pp. 1-24, 2010, DOI:10.3970/cmes.2010.068.001

Abstract Geometrically nonlinear static analysis of an anisotropic thick plate resting on nonlinear two-parameter elastic foundations has been studied. The plate formulation is based on first-order shear deformation theory (FSDT). The governing equation of bending for rectangular orthotropic thick plate is derived by using von Karman equation. The nonlinear static deflections of orthotropic plates on elastic foundation are investigated using the discrete singular convolution method. The effects of foundation, material and geometric parameters of orthotropic plates on nonlinear deflections are investigated. More >

B.W. Kim¹, H.G. Sung¹, S.Y. Hong¹, H.J. Jung²

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.1, pp. 29-46, 2010, DOI:10.3970/cmes.2010.063.029

Abstract This paper numerically investigates the behavior of sag and tension of inclined catenary structure considering elastic deformation. Equilibrium equation for computing elastic catenary is formulated by employing finite element method (FEM). Minimum potential energy principle and the Lagrange multiplier method are used in the formulation to derive equilibrium equation with constraint condition for catenary length. Since stiffness and loading forces of catenary are dependent on its own geometry, the equilibrium equation is nonlinear. Using the iterative scheme such as fixed point iteration or bisection, equilibrium position and tension are found. Based on the formulation, a Fortran solver is developed in… More >

X.Y. Cui^1,2, G. R. Liu^2,3, G. Y. Li¹, X. Zhao², T.T. Nguyen², G.Y. Sun¹

CMES-Computer Modeling in Engineering & Sciences, Vol.28, No.2, pp. 109-126, 2008, DOI:10.3970/cmes.2008.028.109

Abstract A smoothed finite element method (SFEM) is presented to analyze linear and geometrically nonlinear problems of plates and shells using bilinear quadrilateral elements. The formulation is based on the first order shear deformation theory. In the present SFEM, the elements are further divided into smoothing cells to perform strain smoothing operation, and the strain energy in each smoothing cell is expressed as an explicit form of the smoothed strain. The effect of the number of divisions of smoothing cells in elements is investigated in detail. It is found that using three smoothing cells for bending strain energy integration and one… More >

P. H. Wen¹, Y. C. Hon²

CMES-Computer Modeling in Engineering & Sciences, Vol.21, No.3, pp. 177-192, 2007, DOI:10.3970/cmes.2007.021.177

Abstract In this paper, we perform a geometrically nonlinear analysis of Reissner-Mindlin plate by using a meshless collocation method. The use of the smooth radial basis functions (RBFs) gives an advantage to evaluate higher order derivatives of the solution at no cost on extra-interpolation. The computational cost is low and requires neither the connectivity of mesh in the domain/boundary nor integrations of fundamental/particular solutions. The coupled nonlinear terms in the equilibrium equations for both the plane stress and plate bending problems are treated as body forces. Two load increment schemes are developed to solve the nonlinear differential equations. Numerical verifications are… More >

K. Ijima¹, H. Obiya¹, S. Iguchi², S. Goto²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.2, pp. 239-248, 2003, DOI:10.3970/cmes.2003.004.239

Abstract Defining element coordinates in space frame, element end deformations become statically clear from the energy principle. Therefore, the deformations can be expressed by nodal displacement without any approximation. The paper indicates that the exact expressions of the deformations and the geometrical stiffness strictly based on the equations makes large displacement analysis of space frame possible with robustness on the computation. More >

K.Yu. Volokh¹

CMES-Computer Modeling in Engineering & Sciences, Vol.2, No.3, pp. 389-400, 2001, DOI:10.3970/cmes.2001.002.389

Abstract A computational framework is described for modeling pin-jointed structures comprising unilateral cable members and slender struts. The deep postbuckling behavior of struts is considered by means of 'elastica' analytical approximation. Prestressing is allowed. The proposed approach is incorporated into equilibrium path following procedures and illustrated in numerical examples. More >