Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (26)
  • Open Access

    ARTICLE

    High-Performance 3D Hybrid/Mixed, and Simple 3D Voronoi Cell Finite Elements, for Macro- & Micro-mechanical Modeling of Solids, Without Using Multi-field Variational Principles

    P. L. Bishay1, S.N. Atluri1

    CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.1, pp. 41-98, 2012, DOI:10.3970/cmes.2012.084.041

    Abstract Higher-order two-dimensional as well as low and higher-order three-dimensional new Hybrid/Mixed (H/M) finite elements based on independently assumed displacement, and judiciously chosen strain fields, denoted by HMFEM-2, are developed here for applications in macro-mechanics. The idea of these new H/M finite elements is based on collocating the components of the independent strain field, with those derived from the independently assumed displacement fields at judiciously and cleverly chosen collocation points inside the element. This is unlike the other techniques used in older H/M finite elements where a two-field variational principle was used in order to enforce both equilibrium and compatibility conditions… More >

  • Open Access

    ARTICLE

    Development of T-Trefftz Four-Node Quadrilateral and Voronoi Cell Finite Elements for Macro- & Micromechanical Modeling of Solids

    L. Dong1, S. N. Atluri2

    CMES-Computer Modeling in Engineering & Sciences, Vol.81, No.1, pp. 69-118, 2011, DOI:10.3970/cmes.2011.081.069

    Abstract In this paper, we explore three different ways of developing T-Trefftz finite elements of quadrilateral as well as polygonal shapes. In all of these three approaches, in addition to assuming an inter-element compatible displacement field along the element boundary, an interior displacement field for each element is independently assumed as a linear combination of T-Trefftz trial functions. In addition, a characteristic length is defined for each element to scale the T-Trefftz modes, in order to avoid solving systems of ill-conditioned equations. The differences between these three approaches are that, the compatibility between the independently assumed fields at the boundary and… More >

  • Open Access

    ARTICLE

    A Unified Approach to Numerical Modeling of Fully and Partially Saturated Porous Materials by Considering Air Dissolved in Water

    D. Gawin1, L. Sanavia2

    CMES-Computer Modeling in Engineering & Sciences, Vol.53, No.3, pp. 255-302, 2009, DOI:10.3970/cmes.2009.053.255

    Abstract This paper presents a unified mathematical approach to model the hydro-thermo-mechanical behavior of saturated and partially saturated porous media by considering the effects of air dissolved in liquid water. The model equations are discretized by means of the Finite Element method. A correspondingly updated code is used to analyze two examples; the first one is the well known Liakopoulos test, i.e. the drainage of liquid water from a 1m column of sand, which is used to validate numerically the model here developed. As second example, a biaxial compression test of undrained dense sands where cavitation takes place at strain localization… More >

  • Open Access

    ARTICLE

    A Micromechanical Model for Polycrystal Ferroelectrics with Grain Boundary Effects

    K. Jayabal, A. Arockiarajan, S.M. Sivakumar1

    CMES-Computer Modeling in Engineering & Sciences, Vol.27, No.1&2, pp. 111-124, 2008, DOI:10.3970/cmes.2008.027.111

    Abstract A three dimensional micromechanically motivated model is proposed here based on firm thermodynamics principles to capture the nonlinear dissipative effects in the polycrystal ferroelectrics. The constraint imposed by the surrounding grains on a subgrain at its boundary during domain switching is modeled by a suitable modification of the switching threshold in a subgrain. The effect of this modification in the dissipation threshold is studied in the polycrystal behavior after due correlation of the subgrain behavior with the single crystal experimental results found in literature. Taking into consideration, all the domain switching possibilities, the volume fractions of each of the variants… More >

  • Open Access

    ARTICLE

    A Coupled Thermo-Mechanical Model for Simulating the Material Failure Evolution Due to Localized Heating

    Z. Chen1,2, Y. Gan1, J.K. Chen2

    CMES-Computer Modeling in Engineering & Sciences, Vol.26, No.2, pp. 123-138, 2008, DOI:10.3970/cmes.2008.026.123

    Abstract A coupled thermo-mechanical constitutive model with decohesion is proposed to simulate the material failure evolution due to localized heating. A discontinuous bifurcation analysis is performed based on a thermoviscoplasticity relation to identify the transition from continuous to discontinuous failure modes as well as the orientation of the discontinuous failure. The thermo-mechanical model is then implemented within the framework of the Material Point Method (MPM) so that the different gradient and divergence operators in the governing differential equations could be discretized in a single computational domain and that continuous remeshing is not required with the evolution of failure. The proposed model-based… More >

  • Open Access

    ARTICLE

    A Discrete Fourier Transform Framework for Localization Relations

    D.T. Fullwood1, S.R. Kalidindi2, B.L. Adams1, S. Ahmadi1

    CMC-Computers, Materials & Continua, Vol.9, No.1, pp. 25-40, 2009, DOI:10.3970/cmc.2009.009.025

    Abstract Localization relations arise naturally in the formulation of multi-scale models. They facilitate statistical analysis of local phenomena that may contribute to failure related properties. The computational burden of dealing with such relations is high and recent work has focused on spectral methods to provide more efficient models. Issues with the inherent integrations in the framework have led to a tendency towards calibration-based approaches. In this paper a discrete Fourier transform framework is introduced, leading to an extremely efficient basis for the localization relations. Previous issues with the Green's function integrals are resolved, and the method is validated against finite element… More >

Displaying 21-30 on page 3 of 26. Per Page