Micromechanics of fibrous composites subjected to combined shear and thermal loading using a truly meshless method

Abstract

In this study, a micromechanical model is presented to study the combined normal, shear and thermal loading of unidirectional (UD) fiber reinforced composites. An appropriate truly meshless method based on the integral form of equilibrium equations is also developed. This meshless method formulated for the generalized plane strain assumption and employed for solution of the governing partial differential equations of the problem. The solution domain includes a representative volume element (RVE) consists of a fiber surrounded by corresponding matrix in a square array arrangement. A direct interpolation method is employed to enforce the appropriate periodic boundary conditions for the combined thermal, transverse shear and normal loading. The fully bonded fiber-matrix interface condition is considered and the displacement continuity and traction reciprocity are imposed to the fiber-matrix interface. Predictions show excellent agreement with the available experimental, analytical and finite element studies. Comparison of the CPU time between presented method and the conventional meshless local Petrov-Galerkin (MLPG) shows significant reduction of the computational time. The results of this study also revealed that the presented model could provide highly accurate predictions with relatively small number of nodes and less computational time without the complexity of mesh generation.

Micromechanical analysis of unidirectional composites using a least-squares-based differential quadrature element method

“…The overall transverse Young's modulus of the boron/aluminum composite (E c T ) is calculated using three different methods including the presented LSDQEM, FEM (ANSYS), and meshless method [Ahmadi and Aghdam 2010]. The CPU times for these methods are tabulated in Table 1 seen that the number of nodes and the CPU time for LSDQEM are significantly less than for the other two methods which implies efficiency for the presented method.…”

“…Both numerical [Adams and Doner 1967;Adams 1970;Eischen and Torquato 1993;Nedele and Wisnom 1994;Sun and Vaidya 1996;Aghdam et al 2000;2001;Ahmadi and Aghdam 2010] and analytical [Eshelby 1957;Hashin and Rosen 1964;Hill 1965;Uemura et al 1979;Mikata and Taya 1985;Nairn 1985;Aboudi 1987;1989;Nimmer 1990;Robertson and Mall 1993;Aghdam and Dezhestan 2005] micromechanical models have been used to predict the elastic, plastic, and thermal properties of composite materials and their responses to different thermal and mechanical loading conditions.…”

“…Numerical models include finite difference [Adams and Doner 1967], finite element [Adams 1970;Nedele and Wisnom 1994;Sun and Vaidya 1996;Aghdam et al 2000;2001], boundary element [Eischen and Torquato 1993], and, more recently, meshless [Ahmadi and Aghdam 2010] methods. Among the earliest finite element models, one can refer to [Adams 1970], covering the inelastic behavior of composites subjected to transverse normal loading using a plane strain finite element approach.…”

Analysis of Strain Field Heterogeneity at the Microstructure Level and Inverse Identification of Composite Constituents by Means of Digital Image Correlation

“…The most versatile and widely used numerical method for analysis of the deformation behavior of composites at the microstructural level is the finite element method (FEM) [6][7][8][9]. The other numerical methods which can be used for this purpose are the boundary element method (BEM) [10,11] and meshless methods [12,13]. Recently also experimental optical methods have been applied for measuring the deformation behavior at the microstructural level.…”