H. Zheng¹, X. Peng^1,2,3, N. Hu^1,4

CMES-Computer Modeling in Engineering & Sciences, Vol.86, No.6, pp. 505-532, 2012, DOI:10.3970/cmes.2012.086.505

Abstract The static and kinematic shakedown of a functionally graded plate (FGP) is analyzed. The FGP is subjected coupled constant mechanical load and cyclically varying temperature. The FGP is composed of elastoplastic matrix and elastic particles, with the particle volume fraction varying along its thickness. The thermal and mechanical properties and their distributions are evaluated with a mean filed approach, which is based on the Eshelby's inclusion theory and takes into account directly the interaction between particles. The FGP is assumed to be separated into a number of thin layers, the thermal and mechanical properties in… More >

Biao Zhou^1,2,3, Xiong yao Xie^1,2, Yeong Bin Yang⁴, Jing Cai Jiang³

CMES-Computer Modeling in Engineering & Sciences, Vol.86, No.4, pp. 321-348, 2012, DOI:10.3970/cmes.2012.086.321

Abstract The vibration-based SHM (Structure Health Monitoring) system has been successfully used in bridge and other surface civil infrastructure. However, its application in operation tunnels remains a big challenge. The reasons are discussed in this paper by comparing the vibration characteristics of the free tunnel structure and tunnel-soil coupled system. It is revealed that all the correlation characteristics of the free tunnel FRFs (Frequency Response Function spectrum) will vanish and be replaced by a coupled resonance frequency when the tunnel is surrounded by soil. The above statement is validated by field measurements. Moreover, the origin of More >

M.G. Armentano¹, C. Padra², R. Rodríguez³, M. Scheble²

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.4, pp. 359-382, 2012, DOI:10.3970/cmes.2012.084.359

Abstract In this paper we propose an hp finite element method to solve a two-dimensional fluid-structure vibration problem. This problem arises from the computation of the vibration modes of a bundle of parallel tubes immersed in an incompressible fluid. We use a residual-type a posteriori error indicator to guide an hp adaptive algorithm. Since the tubes are allowed to be different, the weak formulation is a non-standard generalized eigenvalue problem. This feature is inherited by the algebraic system obtained by the discretization process. We introduce an algebraic technique to solve this particular spectral problem. We report More >

M. Koyuncu¹, F. Y. Ikikat¹, G. C. Icoz², B. Baranoglu³, A. Yazici²

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.1, pp. 13-26, 2012, DOI:10.3970/cmes.2012.084.013

Abstract A parallel dual reciprocity boundary element method solution to thermoelasticity and thermoviscoelasticity problems is proposed. The DR-BEM formulation is given in Fourier Transform Space where the Time Space solutions are obtained through inverse Fourier Transform. The parallellization of the code is achieved through solving each frequency at a distinct computational node. The implemented parallel code is tested on 64-core IBM blade servers and it is seen that a linear speed-up is achieved. More >

Aravind Sathyanarayana^a, Pramod Warrier^b, Yogendra Joshi^a,*, Amyn Teja^b

Frontiers in Heat and Mass Transfer, Vol.2, No.4, pp. 1-7, 2011, DOI:10.5098/hmt.v2.4.3007

Abstract Electrical and chemical compatibility requirements of electronic components pose significant constraints on the choice of liquid coolants. Dielectric coolants such as Novec fluids and fluoroinerts are plagued by poor thermal properties. This necessitates the development of new heat transfer fluids. In this study we examine mixture formulations that provide an avenue for enhancing the properties of existing heat transfer fluids. Mixture formulations of Novec fluid (HFE 7200) with Methanol and Ethoxybutane are considered. Pool boiling experiments are performed on a copper nanowire surface. The results show an improvement of 24% and 11% in the CHF More >

Martínez-Rubin de Celis E¹, E Rivas-Robles², L Martínez-Corral³, J Frías-Ramírez¹, J Orozco-Vidal¹, M Fortis-Hernández¹, MA Segura Castruita¹

Phyton-International Journal of Experimental Botany, Vol.80, pp. 189-192, 2011, DOI:10.32604/phyton.2011.80.189

Abstract Soil compaction or increase of soil bulk density (Da) as a result of applied loads is expressed as an increase in soil bulk density and soil resistance to penetration. Factors in soil compaction due to vehicular traffic include: the amount of load, soil moisture content and the number of passes over the land. Soil compaction results in the formation of layers that can limit or delay (1) the aeration process; (2) root penetration and infiltration; (3) absorption capacity and soil water retention; (4) nutrient movement; (5) heat transfer, and (6) seedling emergency. At the same… More >

Hanxing Zhu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 131-132, 2011, DOI:10.3970/icces.2011.017.131

Abstract This paper aims to study the size-dependent elastic properties of micro- and nano-sized open-celled foams. To simplify the analysis, we use perfect regular body-centered cubic structure (i.e. BCC foam), which has cubic symmetry and only three independent elastic constants. Taking strut bending, twisting and axial compression/stretching as the deformation mechanisms, Zhu, Knott and Mills (JMPS, V45, pp. 319-343, 1997) have obtained closed form results of all the three independent elastic constants (i.e. the Young's modulus E11 , the shear modulus G12 and the Poisson ratio v12 ) as functions of the bending stiffness, the torsional… More >

Sheng Sun, Joseph T. Y. Wong, Tong-Yi Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.017.047

Abstract Micro/nano structures formed via self-assembly of biological macromolecules, such as DNA and RNA, have potential applications as building units in micro/nano/bio-devices. The self-assembled structures of biological macromolecules can be manipulated by applying electric field. Here we demonstrate such manipulation by using coarse-grained molecular dynamics simulations. Starting from randomly distributed CG DOPE lipids and polarizable water molecules, we studied the self-assembled structures in different hydration levels of lipid (the number of water molecules per lipid) and different strength of external electric fields. When the hydration level of lipid was 24 water per lipid (w/l) or 36… More >

Zhi Xu, Yoshio Bando, Lei Liu, Wenlong Wang, Xuedong Bai, Dmitri Golberg

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 41-42, 2011, DOI:10.3970/icces.2011.017.041

Abstract A specially designed suspended graphene oxide (GO) device has been fabricated and investigated in a transmission electron microscope (TEM)-scanning tunneling microscopy (STM) based setup. The detailed study of step-by-step slow reduction of an individual GO sheet under current flow and thereby Joule heating, while in-parallel performing conductivity measurements, atomic structure imaging, chemical composition, and bonding alternations tracing have been performed. As monitored by electron energy core loss spectroscopy, the oxygen content is tuned from that peculiar to a pristine GO, i.e. 23.8 at.%, to oxygen-free pure graphene. Six orders of magnitude conductance rise is achieved… More >

LIN Xiao-Ping, LEI Zhen-Kun, LIU Zeng-Hua, WU Zhan-Jun

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.1, pp. 29-30, 2011, DOI:10.3970/icces.2011.017.029

Abstract Recently, a technology named ultrasonic guided wave has a rapid development and wide application. It is more and more popular for the advantage compared with traditional detection. An enormous amount of work has contributed to our current understanding of wave propagation. The case of a hollow cylinder loaded by the outside liquid has been considered by Rose et al. Kwun investigated the propagation of guided waves in water filled pipes. C. Aristegui discussed propagation of guided waves in fluid-filled pipe surrounded by different fluids. Lafleur and Shields have studied the propagation of low frequency modes… More >