Ligia Munteanu¹, Veturia Chiroiu¹, Valeria Mosnegutu¹

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 137-156, 2011, DOI:10.3970/cmc.2011.026.137

Abstract In this paper, yet another method for evaluating the elastic modulus for human bones is introduced and investigated. This method adopts the Jankowski and Tsakalakos strain energy function in which, the Born-Mayer energy term is the predominant term for calculations the elastic constants. By taking accounts the directional aspects of the spatial structure of bones, we obtain different values for the Young's modulus depending on the direction of the applied force with respect to the material's structure. The inverse problem analyzed in this paper is solved by inversion of the experimental data. An efficient stopping More >

De-Shin Liu¹, Zhen-Wei Zhuang¹, Shaw-Ruey Lyu^2,3, Cho-Liang Chung⁴, Pai-Chen Lin¹

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 111-136, 2011, DOI:10.3970/cmc.2011.026.111

Abstract This study proposes a two-dimensional heterogeneous hybrid moisture element method (HHMEM) for modeling transient moisture diffusion in permeable fiber-reinforced polymer composites.
The HHMEM scheme is based on a heterogeneous hybrid moisture element(HHME), with properties determined through an equivalent hybrid moisture capacitance/conductance matrix. This matrix was calculated using the conventional finite element formulation in space discretization as well as the θ-method in time discretization with similar mass/stiffness properties and matrix condensing operations. A coupled HHME-FE scheme was developed and implemented in computer code MATLAB in order to analyze the transient moisture diffusion characteristics of composite materials containing multiple… More >

Surkay D. Akbarov^1,2, Tamer Kepceler¹, M. Mert Egilmez¹, Ferhat Dikmen¹

CMC-Computers, Materials & Continua, Vol.26, No.2, pp. 91-110, 2011, DOI:10.3970/cmc.2011.026.091

Abstract This paper studies the torsional wave dispersion in the hollow bi-material compounded cylinder with finite initial strains. The investigations are carried out within the scope of the piecewise homogeneous body model with the use of the three-dimensional linearized theory of elastic waves in initially stressed bodies. The mechanical relations of the materials of the cylinders are described through the harmonic potential. The numerical results on the influence of the initial stretching or compression of the cylinders along the torsional wave propagation direction are presented and discussed More >

M. Morii¹, N. Hu^1,2, H. Fukunaga³, J.H. Li¹, Y.L. Liu¹, S. Atobe³, Alamusi³, J.H. Qiu⁴

CMC-Computers, Materials & Continua, Vol.26, No.1, pp. 37-66, 2011, DOI:10.3970/cmc.2011.026.037

Abstract Lamb wave tomography (LWT) is a potential and efficient technique for non-destructive tomographic reconstruction of damage images in structural components or materials. A new two-stage inverse algorithm with a small amount of scanning data for quickly reconstructing damage images in aluminum and CFRP laminated plates was proposed in this paper. Due to its high sensitivity to damages, the amplitude decrease of transmitted Lamb waves after travelling through the inspected region was employed as a key signal parameter related to the attenuation of Lamb waves in propagation routes. A through-thickness circular hole and a through-thickness elliptical More >

Y. Zhang^1,2, Z.H. Xiang^1,3

CMC-Computers, Materials & Continua, Vol.26, No.1, pp. 19-36, 2011, DOI:10.3970/cmc.2011.026.019

Abstract Vibration based damage detection methods play an important role in the maintenance of beam structures such as bridges. However, most of them require the accurate measurement of structural mode shapes, which may not be easily satisfied in practice. Since the measurement of frequencies is more accurate than that of mode shapes, this paper proposes a frequency shift curve (FSC) method, based on the equivalence between the FSC due to auxiliary mass and the mode shape square, which has been demonstrated to be effective in structural damage detection. Two damage indices based on the FSC are More >

V.K. Tewary¹, M. D. Vaudin²

CMC-Computers, Materials & Continua, Vol.25, No.3, pp. 265-290, 2011, DOI:10.3970/cmc.2011.025.265

Abstract A semicontiuum Green's-function-based model is proposed for analysis of averaged mechanical characteristics of Si_xGe_{1 - x}. The atomistic forces in the model are distributed at discrete lattice sites, but the Green's function is approximated by the continuum GF in the far field and by the averaged lattice GF in the near field. Averaging is achieved by replacing Si and Ge atoms by identical hypothetical atoms that are x fraction Si and (1-x) fraction Ge. The parameters of the model are derived using the atomistic model from the interatomic potential between the hypothetical atoms. The interatomic potential… More >

Jiun-Yu Wu^1,2, Chih-Wen Chang³

CMC-Computers, Materials & Continua, Vol.25, No.3, pp. 215-238, 2011, DOI:10.3970/cmc.2011.025.215

Abstract In this paper, we employ the differential quadrature method (DQM) to tackle the inverse heat conduction problem (IHCP) of heat source. These advantages of this numerical approach are that no a priori presumption is made on the functional form of the estimates, and that evaluated heat source can be obtained directly in the calculation process. Seven examples show the effectiveness and accuracy of our algorism in providing excellent estimates of unknown heat source from the given data. We find that the proposed scheme is applicable to the IHCP of heat source. Even though the noise More >

Wen-Hwa Chen^1,2, Chun-Hung Wu¹, Hsien-Chie Cheng^3,4,5

CMC-Computers, Materials & Continua, Vol.25, No.3, pp. 195-214, 2011, DOI:10.3970/cmc.2011.025.195

Abstract The study aims at investigating the linear and volumetric thermal expansion coefficients (CTEs) at temperature below the Debye temperature and phase transformation behaviors at atmospheric pressure of carbon fullerenes, i.e., C₆₀, C₇₀ and C₈₀, through a modified Nosé-Hoover (NH) thermostat method incorporated with molecular dynamics (MD) simulation. The calculated results are compared with those obtained from the standard NH and "massive" NHC (MNHC) thermostats and also with the literature experimental and theoretical data. Results show that at temperature below the Debye temperature, the CTEs of the fullerene molecules would significantly decrease with a decreasing temperature and tend… More >

W. Liu, X. Y. Su, Y. R. An, K. F. Huang¹

CMC-Computers, Materials & Continua, Vol.25, No.2, pp. 177-194, 2011, DOI:10.3970/cmc.2011.025.177

Abstract Local buckling is a typical failure mode of large scale composite wind turbine blades. A procedure for predicting the onset and location of local buckling of composite wind turbine blades under aerodynamic loads is proposed in this paper. This procedure is distinct from its counterparts in adopting the pressure distributions obtained from Computational Fluid Dynamics (CFD) calculations as the loads. The finite element method is employed to investigate local buckling resistance of the composite blade. To address the mismatch between the unstructured CFD grids of the blade surface and the finite shell elements used during More >

R. Djebali¹, B. Pateyron², M. ElGanaoui³

CMC-Computers, Materials & Continua, Vol.25, No.2, pp. 159-176, 2011, DOI:10.3970/cmc.2011.025.159

Abstract Axisymetric lattice Boltzmann (LB) model is developed to investigate the interaction of momentum and heat between plasma hot gas and Alumina powders. The plasma flow is simulated using a double population lattice Boltzmann model and the plasma-particles interaction is modeled based on a Lagrangian approach for the motion and heat transfer equations. The present results show that the LB method is an efficient and powerful tool to comprehend and explain the very high complexity of the plasma jet physics as well as it preserves effectively the computational cost. The present results for the centerline temperature More >