G. Q. Xie¹, J. P. Wang², Q. L. Zhang¹

CMC-Computers, Materials & Continua, Vol.48, No.2, pp. 103-117, 2015, DOI:10.3970/cmc.2015.048.103

Abstract Small-scale effect on the static deflection of a clamped graphene sheet and influence of the helical angle of the clamped graphene sheet on its static deflection are investigated. Static equilibrium equations of the graphene sheet are formulated based on the concept of nonlocal elastic theory. Galerkin method is used to obtain the classical and the nonlocal static deflection from Static equilibrium equations , respectively. The numerical results show that the static deflection and small-scale effect of a clamped graphene sheet is affected by its small size and helical angle. Small-scale effect will decrease with increase of the length and width… More >

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 179-201, 2015, DOI:10.3970/cmc.2015.047.179

Abstract Discontinuous smoothed particle hydrodynamics (DSPH) method based on traditional SPH method, which can be used to simulate discontinuous physics problems near interface or boundary. Previous works showed that DSPH method has a good application prospect [Xu et al, 2013], but further verification and improvement are demanded. In this paper, we investigate the accuracy of DSPH method by some numerical models. Moreover, to improve the accuracy of DSPH method, first order and second order multidimensional RDSPH methods are proposed by following the idea of restoring particle consistency in SPH (RSPH) method which has shown good results in the improvement of particle… More >

M. C. Ray¹, L. Dong², S. N. Atluri³

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 143-177, 2015, DOI:10.3970/cmc.2015.047.143

Abstract This paper is concerned with the development of new simple 4-noded locking-alleviated smart finite elements for modeling the smart composite beams. The exact solutions for the static responses of the overall smart composite beams are also derived for authenticating the new smart finite elements. The overall smart composite beam is composed of a laminated substrate conventional composite beam, and a piezoelectric layer attached at the top surface of the substrate beam. The piezoelectric layer acts as the actuator layer of the smart beam. Alternate finite element models of the beams, based on an “equivalent single layer high order shear deformation… More >

Ligia Munteanu¹, Dan Dumitriu¹, Veturia Chiroiu¹, Cornel Bri¸san², Doina Marin¹

CMC-Computers, Materials & Continua, Vol.46, No.2, pp. 79-103, 2015, DOI:10.3970/cmc.2015.046.079

Abstract A flexible finger with muscles made of Nitinol wires and the skin made of auxetic material is analyzed from the tactile sensing point of view. The recognizing of the shape and texture of 3D objects is performed by simulation the action of an array of nanopiezotronic transistors integrated into the skin. The array of nanopiezotronic transistors makes possible the detection of the pressure-induced changes in the auxetic skin. The shape and texture of the objects is best estimated by determining the surface and texture as an n-ellipsoid defined by 12 parameters. An inverse problem is solved in order to find… More >

Ligia Munteanu¹, Veturia Chiroiu¹, Viorel Şerban²

CMC-Computers, Materials & Continua, Vol.42, No.3, pp. 175-204, 2014, DOI:10.3970/cmc.2014.042.175

Abstract The paper introduces a new alternative towards fabrication of auxetic metamaterials (materials with negative Poisson’s ratio) controlled by geometric transformations. These transformations are derived from the theory of small (infinitesimal) elastic deformation superimposed on finite elastic deformations. By using this theory, a cylindrical region filled with initial deformed foam is transformed through deformation into a cylindrical shell region filled with auxetic metamaterial. As an example, the realization of the seismic cloak device becomes a practical possibility. More >

Qiubao Ouyang¹, Di Zhang^1,2, Xinhai Zhu³, Zhidong Han³

CMC-Computers, Materials & Continua, Vol.41, No.1, pp. 37-54, 2014, DOI:10.3970/cmc.2014.041.037

Abstract The present work is to investigate the failure mechanisms in the deformation of silicon carbide (SiC) particle reinforced aluminum Metal Matrix Composites (MMCs). To better deal with crack growth, a new numerical approach: the MLPG-Eshelby Method is used. This approach is based on the meshless local weak-forms of the Noether/Eshelby Energy Conservation Laws and it achieves a faster convergent rate and is of good accuracy. In addition, it is much easier for this method to allow material to separate in the material fracture processes, comparing to the conventional popular FEM based method. Based on a statistical method and physical observations,… More >

Raveendranath U. Nair, Preethi D.S, R. M. Jha

CMC-Computers, Materials & Continua, Vol.40, No.2, pp. 131-144, 2014, DOI:10.3970/cmc.2014.040.131

Abstract Controllable artificial dielectrics are used in the design of radomes to enhance their electromagnetic (EM) performance. The fabrication of such radome wall structures with controllable dielectric parameters seems to be an arduous task. Further even minor fluctuations of dielectric properties of radome wall due to fabrication uncertainties tend to result in drastic degradation of radome performance parameters. In the present work, a novel inhomogeneous radome with graded variation of dielectric parameters is proposed which limits the constraints on fabrication and facilitates excellent EM performance characteristics. This radome wall consists of five dielectric layers cascaded such that the middle layer has… More >

Shiv Narayan¹, Latha S.¹ and R M Jha¹

CMC-Computers, Materials & Continua, Vol.39, No.3, pp. 217-230, 2014, DOI:10.3970/cmc.2014.039.217

Abstract The EM analysis of multi-layered metamaterial based radar absorbing structure (RAS) with dual-band characteristics in millimeter wave frequency regime has been carried out in this paper using transmission line transfer matrix (TLTM) method for TE and TM polarizations. The proposed metamaterial-based RAS exhibits dual-band characteristics at centre frequencies 120 GHz and 175 GHz with very low power reflection. It absorbs more than 90% power of incidence wave over the frequency range from 111-131 GHz at first resonance and from 164.5-185 GHz at second resonance without metal backing plate, which is desirable for stealth applications. It also showed very low (<… More >

J.B. Niu¹, L.L. Li², Q. Xu¹, Z.H. Xia^1,3

CMC-Computers, Materials & Continua, Vol.38, No.1, pp. 31-41, 2013, DOI:10.3970/cmc.2013.038.031

Abstract Crack deflection and penetration at the interface of multi-wall carbon nanotube/amorphous carbon composites were studied via molecular dynamics simulations. In-situ strength of double-wall nanotubes bridging a matrix crack was calculated under various interfacial conditions. The structure of the nanotube reinforcement -ideal multi-wall vs. multi-wall with interwall sp³ bonding - influences the interfacial sliding and crack penetration. When the nanotube/matrix interface is strong, matrix crack penetrates the outermost layer of nanotubes but it deflects within the nanotubes with certain sp³ interwall bond density, resulting in inner wall pullout. With increasing the sp³ interwall bond density, the fracture mode becomes brittle; the… More >

Ridha Djebali¹, Mohsen Toujani², Bernard Pateyron³

CMC-Computers, Materials & Continua, Vol.37, No.3, pp. 147-160, 2013, DOI:10.3970/cmc.2013.037.147

Abstract In this paper a study of the atmospheric plasma spraying process was conducted. The Jets&Poudres code was used to solve the partial differential equations for the conservation of mass, momentum and energy involved in the problem together with the K-e turbulent model. The Taguchi technique was used to study the influence of processing factors on droplet impact properties obtained on dense zirconia (ZrO₂) under H₂Ar75% plasma gas that allow optimal functioning condition. The test of the operating parameters for the studied ranges showed that the "thermal power" factor plays a key role on the state of sprayed powder. It was… More >