Influence of First to Second Gradient Coupling Tensors Terms with Surface Effects on the Wave Propagation of 2D Network Materials

International audienc

Finite Element Investigation of Effective Moduli of Transversely Isotropic Thermoelastic Materials with Nanoscale Porosity

Using the methods of effective moduli and finite elements, the effective properties of nanoporous thermoelastic transversely isotropic materials were studied for simple random and for closed structures of porosity. Nanoscale effects were modelled in the framework of the Gurtin-Murdoch model of interface stresses and of the high conductivity model. The modelling and solution of homogenization problems was performed in the ANSYS package, while structures of representative volumes with closed porosity were created in the ACELAN-COMPOS package. The effect of porosity, types of representative volumes and pore sizes on the values of the effective modules of nanoporous titanium is analysed. © 2020, Springer Nature Switzerland AG

Homogenization of Dispersion-Strengthened Thermoelastic Composites with Imperfect Interfaces by Using Finite Element Technique

The paper describes the homogenization procedure for a two-phase mixture composite that consists of two isotropic thermoelastic materials. It is assumed that the special interface conditions are held on the boundary between the phases, where the stress and the thermal flux jump over the interphase boundary are equal to the surface stresses and thermal flux at the interface. Such boundary conditions are used to describe the nanoscale effects in thermoelastic nanodimensional bodies and nanocomposites. The homogenization problems are solved using the approach of the effective moduli method, the finite element method and the algorithm for generating the representative volume of cubic finite elements with random distribution of element material properties. As a numerical example, a mixture wolfram-copper composite is considered, where the interface conditions are simulated by surface membrane and thermal shell elements

A fast and accurate analysis of the interacting cracks in linear elastic solids

2008-2009 > Academic research: refereed > Publication in refereed journa

Mathematical models and finite element approaches for nanosized piezoelectric bodies with uncoulped and coupled surface effects

In this chapter the dynamic problems for piezoelectric nanosized bodies with account for coupled damping and surface effects are considered. For these problems we propose new mathematical model which generalizes the models of the elastic medium with damping in sense of the Rayleigh approach and with surface effects for the cases of piezoelectric materials. Our model of attenuation and surface effects has coupling properties between mechanical and electric fields, both for the damping terms and constitutive equations for piezoelectric materials on the surface. For solving the problems stated the finite element approximations are discussed. A set of effective finite element schemes is examined for finding numerical solutions of week statements for nonstationary problems, steady-state oscillation problems, modal problems and static problems within the framework of modelling of piezoelectric nanosized materials with damping and surface effects. For transient and harmonic problems, we demonstrate that the proposed models allow the use of the mode superposition method. In addition, we note that for transient and static problems we can use efficient finite element algorithms for solving the systems of linear algebraic equations with symmetric quasi-definite matrices both in the case of uncoupled surface effects and in the case of coupled surface effects