Open Access
ARTICLE
Qifeng Fan1, Yaping Zhang2, Leiting Dong1,3, Shu Li1, Satya N. Atluri4
CMC-Computers, Materials & Continua, Vol.47, No.2, pp. 65-88, 2015, DOI:10.3970/cmc.2015.047.065
Abstract A very simple displacement-based hexahedral 32-node element (denoted as DPH32), with over-integration in the thickness direction, is developed in this paper for static and dynamic analyses of laminated composite plates and shells. In contrast to higher-order or layer-wise higher-order plate and shell theories which are widely popularized in the current literature, the proposed method does not develop specific theories of plates and shells with postulated kinematic assumptions, but simply uses the theory of 3-D solid mechanics and the widely-available solid elements. Over-integration is used to evaluate the element stiffness matrices of laminated structures with an arbitrary number of laminae, while… More >
Open Access
ARTICLE
Bui Duc Thuan1,2, Wong Yonghui2, Chua Kian Jon2, Ng Kim Choon2
CMC-Computers, Materials & Continua, Vol.47, No.2, pp. 89-105, 2015, DOI:10.3970/cmc.2015.047.089
Abstract The cup method and dynamic moisture permeation cell (DMPC) method are two common techniques used to determine the water vapor permeation properties of a membrane. Often, ignoring the resistance of boundary air layers to the transport of water vapor results in the water vapor permeance of the membrane being underestimated in practical tests. The measurement errors are higher with highly permeable membranes. In this study, the two methods were simulated using COMSOL Multiphysics platform and the extent of the error was evaluated. Initial results showed that the error is equally high in both methods. With the correction for the still… More >
Open Access
ARTICLE
P.A. Meroño1, F.C. Gómez2, F. Marín1
CMC-Computers, Materials & Continua, Vol.47, No.2, pp. 107-125, 2015, DOI:10.3970/cmc.2015.047.107
Abstract This work represents a comparative study of Wavelet Transform of angular vibration signal and the traditional Fourier analysis applied to the signals of angular vibration, in one transmission which involve gears. How it is known, the elastic deformation of the material, together with the superficial irregularities of the teeth due to wear, provoke characteristic angular oscillations, which make it possible to distinguish between the regular functioning of a mechanism in good condition and the angular vibrations provoked by wear and the superficial irregularities of teeth in poor condition. However, the character of the vibrations produced in such circumstances means that… More >
Open Access
ARTICLE
Yi Xue1,2, Feng Gao1,2,3, Xingguang Liu4, Xiru Li2
CMC-Computers, Materials & Continua, Vol.47, No.2, pp. 127-141, 2015, DOI:10.3970/cmc.2015.047.127
Abstract In order to study the effect of high pressure water jet cutting technology on the permeability of single coal seam, we use the damage variable to describe the fracture distribution of coal seam, develop the 3-D finite element program based on the damage theory, and then analyze the damage distribution of coal seam after drilling and slotting. Using MTS815 rock mechanics testing system and the permeability test system, we conduct the permeability test and get the relationship between permeability and damage. Based on the damage distribution of coal seam after drilling and slotting and the permeability change law, we analyze… More >