Open Access
ARTICLE
Leiting Dong1,2, Salah H. Gamal3, Satya N. Atluri2,4
CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 1-21, 2013, DOI:10.3970/cmc.2013.037.001
Abstract In this paper, a simple and reliable procedure of stochastic computation is combined with the highly accurate and efficient Trefftz Computational Grains (TCG), for a direct numerical simulation (DNS) of heterogeneous materials with microscopic randomness. Material properties of each material phase, and geometrical properties such as particles sizes and distribution, are considered to be stochastic with either a uniform or normal probabilistic distributions. The objective here is to determine how this microscopic randomness propagates to the macroscopic scale, and affects the stochastic characteristics of macroscopic material properties. Four steps are included in this procedure: (1) using the Latin hypercube sampling,… More >
Open Access
ARTICLE
M. Marin1, S. R. Mahmoud2,3, K. S. Al-Basyouni4
CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 23-37, 2013, DOI:10.3970/cmc.2013.037.023
Abstract Taking advantage of the flexibility of Lagrange’s identity, we prove the uniqueness theorem and some continuous dependence theorems without recourse to any energy conservation law, or to any boundedness assumptions on the constitutive coefficients. Also, we avoid the use of positive definiteness assumptions on the constitutive coefficients, even if these results are related to the difficult mixed problem in elasticity of micromorphic bodies. More >
Open Access
ARTICLE
J. Joseph1, Y. C. Lu1
CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 39-57, 2013, DOI:10.3970/cmc.2013.037.039
Abstract Aligned carbon nanotubes structures are emerging new materials that have demonstrated superior mechanical, thermal, and electrical properties and have the huge potential for a wide range of applications. In contrast with traditional materials whose microstructures are relatively "fixed", the aligned carbon nanotube materials have highly "tunable" structures. Therefore, it is crucial to have a rational strategy to design and evaluate the architectures and geometric factors to help process the optimal nanotube materials. Astructural mechanics based computational modeling is used for designing the aligned carbon nanotubes structures. Part 1 of the papers presents the theory of the computational method as well… More >
Open Access
ARTICLE
J. Joseph1, Y. C. Lu1
CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 59-75, 2013, DOI:10.3970/cmc.2013.037.059
Abstract The aligned carbon nanotube (A-CNT) structure is composed of arrays of individual CNTs grown vertically on a flat substrate. The overall structure and properties of an A-CNTs are highly dependent upon the designs of various architectures and geometric parameters. In Part 2, we have presented the detailed designs and modeling of various aligned carbon nanotube structures. It is found the A-CNT structures generally have much lower modulus than an individual CNT. The reason is due to the high porosity and low density of the A-CNT structures, since the interstitial space between nanotubes is mostly occupied by air. Increasing the nanotube… More >