Cao Zhengzheng¹, Zhou Yuejin^1,2, Zhang Qi¹, Wang Erqian¹

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 203-215, 2015, DOI:10.3970/cmc.2015.047.203

Abstract Gas fracturing technology is the key to the exploration for unconventional petroleum resources and other engineering industries, so the research on the coupled gas-solid-thermal model during rock damage has the important significance to the development of gas fracturing technology. By introducing rock damage variable, the coupled gas-solid-thermal model during rock damage is established in this paper, besides, the rock damage constitutive is written with MATLAB software, which is embedded in the multi-physics coupling software COMSOL in the process of numerical computation. Based on this, the damage rule of rock mass around drilling under high pressure… More >

Jianhang Du^1,2,3, Liang Wang⁴

Molecular & Cellular Biomechanics, Vol.12, No.4, pp. 249-263, 2015, DOI:10.3970/mcb.2015.012.249

Abstract Growing evidences suggest that long-term enhanced external counterpulsation (EECP) treatment can inhibit the initiation of atherosclerotic lesion by improving the hemodynamic environment in aortas. However, whether this kind procedure will intervene the progression of advanced atherosclerotic plaque remains elusive and causes great concern in its clinical application presently. In the current paper, a pilot study combining animal experiment and numerical simulation was conducted to investigate the acute mechanical stress variations during EECP intervention, and then to assess the possible chronic effects. An experimentally induced hypercholesterolemic porcine model was developed and the basic hemodynamic measurement was… More >

Maryam Jazayeri¹, Mohammad Ali Shokrgozar¹, Nooshin Haghighipour^1,2, Reza Mahdian³, Mehdi Farrokhi¹, Shahin Bonakdar¹, FereshtehMirahmadi¹, Tannaz Nourizadeh Abbariki

Molecular & Cellular Biomechanics, Vol.12, No.3, pp. 197-213, 2015, DOI:10.3970/mcb.2015.012.197

Abstract The osseous tissue repair and regeneration have great importance in orthopedic and maxillofacial surgery. Tissue engineering makes it possible to cure different tissue abnormalities using autologous grafts. It is now obvious that mechanical loading has essential role in directing cells to differentiation. In this study, the influence of cyclic uniaxial loading and its combination with chemical factors on expression of osteogenic markers was investigated. Rat bone marrow-derived stem cells were isolated and cultured. In one group cells were maintained in chemical induction medium. In another group cells were subjected to cyclic uniaxial strain with 3%… More >

Heng Zuo^*, Dalin Tang^*,†,‡, Chun Yang^*,§, Glenn Gaudette^¶, Kristen L. Billiar^¶, Pedro J. del Nidok^II

Molecular & Cellular Biomechanics, Vol.12, No.2, pp. 67-85, 2015, DOI:10.3970/mcb.2015.012.067

Abstract Right ventricular (RV) dysfunction is a common cause of heart failure in patients with congenital heart defects and often leads to impaired functional capacity and premature death. Myocardial tissue regeneration techniques are being developed for the potential that viable myocardium may be regenerated to replace scar tissues in the heart or used as patch material in heart surgery. 3D computational RV/LV/Patch models with fluid-structure interactions (FSI) were constructed based on data from a healthy dog heart to obtain local fluid dynamics and structural stress/strain information and identify optimal conditions under which tissue regeneration techniques could… More >

Daisuke Ishihara^1,2, Tomoyoshi Horie¹, Tomoya Niho¹, Akiyoshi Baba³

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.6, pp. 429-452, 2015, DOI:10.3970/cmes.2015.108.429

Abstract In this study, a hierarchal decomposition is proposed to solve the structure- fluid-electrostatic interaction in a microelectromechanical system (MEMS). In the proposed decomposition, the structure-fluid-electrostatic interaction is partitioned into the structure-fluid interaction and the electrostatic field using the iteratively staggered method, and the structure-fluid interaction is split into the structurefluid velocity field and the fluid pressure field using the projection method. The proposed decomposition is applied to a micro cantilever beam actuated by the electrostatic force in air. It follows from the comparisons among the numerical and experimental results that the proposed method can predict More >

Isa Ahmadi¹, M.M. Aghdam²

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.1, pp. 21-48, 2015, DOI:10.3970/cmes.2015.108.021

Abstract In this study, a truly meshless method based on the meshless local Petrov-Galerkin method is formulated for analysis of the elastic-plastic behavior of heterogeneous solid materials. The incremental theory of plasticity is employed for modeling the nonlinearity of the material behavior due to plastic strains. The well-known Prandtl-Reuss flow rule of plasticity is used as the constitutive equation of the material. In the presented method, the computational cost is reduced due to elimination of the domain integration from the formulation. As a practical example, the presented elastic-plastic meshless formulation is employed for micromechanical analysis of More >

X. Wang¹, W.T. Ang^1,2, H. Fan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.2, pp. 81-101, 2015, DOI:10.3970/cmes.2015.107.081

Abstract A micromechanical model is proposed here for estimating the effective stiffness of a pair of parallel microscopically damaged interfaces in a trimaterial under inplane elastostatic deformations. The trimaterial is made of an orthotropic thin layer sandwiched between two orthotropic half-spaces. The microscopically damaged interfaces are modeled using periodically distributed interfacial micro-cracks. The micromechanical model is formulated and numerically solved in terms of hypersingular boundary integro-differential equations. The effects of the width of the thin layer, the micro-crack densities of the two interfaces and the material constants of the thin layer and the two half-spaces on More >

Hui Huang, Hidekazu Murakawa

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.3, pp. 187-201, 2015, DOI:10.3970/cmes.2015.106.187

Abstract Dynamic mesh refining method (DMRM) developed previously was extended to multi-level refinement, and employed to perform thermal-mechanical analysis of fillet welding. The DMRM has been successfully incorporated with another efficient technique, the iterative substructure method (ISM) to greatly enhance the computation speed of welding simulation. The basic concept, hierarchical modeling and computation flowchart are described for the proposed method. A flange-to-pipe welding problem has been solved with a commercial code and the novel method to demonstrate its high accuracy and efficiency. Furthermore, the numerical analysis was performed on a large scale stiffened welding structure, and More >

Y.H. Liu¹, X.X. Xue², J.M.Shen¹

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.2, pp. 197-204, 2015, DOI:10.3970/fdmp.2015.011.195

Abstract Blends of Polyethylene (PE) and modified-oil shale ash (MOSA) with different fractions of MOSA were prepared by the melting blend method. The effects of MOSA content on the rheological and mechanical properties of the blend were properly assessed via direct experimental analysis (more precisely, all rheological measurements were performed using a laboratory-scale XSS-300 torque rheometer with single screw extruder; the temperatures were maintained at 170°C, 180°C and 190°C under continuous extrusion). The prepared samples were observed to display a shear-thinning behaviour. Moreover, with increasing the MOSA content, we found the yield strength of the blends More >

H. Khellafi¹, H.M. Meddah¹, B. Ould Chikh¹, B. Bouchouicha², M. Benguediab², M. Bendouba³

CMC-Computers, Materials & Continua, Vol.49-50, No.1, pp. 31-45, 2015, DOI:10.3970/cmc.2015.049.031

Abstract The polyvinyl chloride PVC is a polymer material widely used for a large variety of applications. The present work focuses on the identification of the physical processes responsible for the mechanical properties of the PVC containing different crystallinities rate applied in large deformation and different strain rates. In order to understand the behavior of the PVC, a thermodynamic modeling is needed. Therefore, the contribution of this approach was demonstrated by experiment and numerical modeling. This comparative study demonstrates that the proposed model provides better agreement with experimental evidence. More >