Vol.12, No.3, 2009-Table of Contents
  • A Computational Approach to Investigate Electromagnetic Shielding Effectiveness of Steel Fiber-Reinforced Mortar
  • Abstract The electromagnetic shielding effectiveness of steel fiber-reinforced mortar was numerically examined in this study. A series of numerical analysis on twenty-seven types of specimens of different diameters, lengths, and volume fractions of fibers were conducted using the FE program HFSS to investigate the effect of the dimensions of steel fibers and the amount of fibers added to the mortar on the shielding effectiveness. S-parameters of some specimens were experimentally measured by the free space method and the experimentally measured S-parameters were compared with those computed in order to verify the present numerical analysis method. It was found that smaller diameters… More
  •   Views:231       Downloads:260        Download PDF
  • Computer Modeling of Ionic Conductivity in Low Temperature Doped Ceria Solid Electrolytes
  • Abstract Solid oxides, such as ceria (CeO2) doped with cations of lower valance, are potential electrolytes for future solid oxide fuel cells. This is due to the theoretically high ionic conductivity at low operation temperature. This paper investigates the feasibility of two potential electrolytes which are samarium-doped ceria (SDC) and gadolinium-doped ceria (GDC) to replace the traditional yttria-stablized zirconia (YSZ). Molecular simulation techniques were employed to study the influence of different dopant concentrations at different operation temperatures on the ionic conductivity from the atomistic perspective. Simulation results show that the optimized ionic conductivity occurs at 11.11mol% concentration using both dopants of… More
  •   Views:237       Downloads:217        Download PDF
  • A General Magnetoelastic Coupling Theory of Deformable Magnetized Medium Including Magnetic Forces and Magnetostriction Effects
  • Abstract From the viewpoint of energy, a general magnetoelastic coupling theory including magnetic forces and magnetostriction effects is proposed for deformable magnetized medium. Firstly, a Taylor series expansion of independent variables of stress and magnetization in the elastic Gibbs free energy function is applied to obtain a polynomial expression; and then based on the magnetoelastic coupling mechanism, appropriate transcendental functions are substituted for some terms in a polynomial constitutive relationship derived by way of substituting the polynomial Gibbs free energy function in thermodynamic equations to achieve a more compact magnetostrictive constitutive relationship. The numerical simulation exhibits that the predicted magnetostrictive strain… More
  •   Views:224       Downloads:196        Download PDF
  • Three-Dimensional Solutions of Functionally Graded Piezo-Thermo-Elastic Shells and Plates Using a Modified Pagano Method
  • Abstract A modified Pagano method is developed for the three-dimensional (3D) coupled analysis of simply-supported, doubly curved functionally graded (FG) piezo-thermo-elastic shells under thermal loads. Four different loading conditions, applied on the lateral surfaces of the shells, are considered. The material properties of FG shells are regarded as heterogeneous through the thickness coordinate, and then specified to obey an exponent-law dependent on this. The Pagano method, conventionally used for the analysis of multilayered composite elastic plates/shells, is modified to be feasible for the present analysis of FG piezo-thermo-elastic plates/shells. The modifications include that a displacement-based formulation is replaced by a mixed… More
  •   Views:220       Downloads:180        Download PDF