Molecular dynamics modeling of structural battery components

A crosslinked polymer based solid electrolyte prototype material –poly(propylene glycol) diacrylate– is studied using the reactive molecular dynamics force field ReaxFF. The focus of the study is the evaluation of the effects of equilibration and added plasticizer (ethylene carbonate) or anion components on Li ion transport properties in the...

Multiscale analysis of damage using dual and primal domain decomposition techniques

In this contribution, dual and primal domain decomposition techniques are studied for the multiscale analysis of failure in quasi-brittle materials. The multiscale strategy essentially consists in decomposing the structure into a number of nonoverlapping domains and considering a refined spatial resolution where needed. In multiscale analysis of...

On the minimization of round-off errors induced by the generalized finite element method (poster)

Benchmarking high order finite element approximations for one-dimensional boundary layer problems

In this article we investigate the application of high order approximation techniques to one-dimensional boundary layer problems. In particular, we use second order differential equations and coupled second order differential equations as case studies. The accuracy and convergence rate of numerical solutions obtained with Lagrange, Hermite, B...

Objective multiscale analysis of random heterogeneous materials

The multiscale framework presented in [1, 2] is assessed in this contribution for a study of random heterogeneous materials. Results are compared to direct numerical simulations (DNS) and the sensitivity to user-defined parameters such as the domain decomposition type and initial coarse scale resolution is reported. The parallel performance of...

Modelling crack initiation and propagation in masonry using the partition of unity method

A mesoscopic masonry model is presented using the partition of unity finite element method. Joints are only explicitly introduced when a critical stress state is exceeded, resulting in a computationally more efficient procedure when compared to models in which all joints are a priori active. The performance of the presented model is demonstrated...

Bridging Scales with a Generalized Finite Element Method

The generalized FEM (GFEM) has been successfully applied to the simulation of dynamic propagating fractures, polycrystalline and fiber-reinforced microstructures, porous materials, etc. A-priori knowledge about the solution of these problems are used in the definition of their GFEM approximation spaces. This leads to more accurate and robust...

Concurrent multiscale analysis of heterogeneous materials

Concurrent multiscale analysis of quasi-brittle heterogeneous materials such as concrete and rock is conducted employing non-overlapping domain decomposition techniques. Initially a coarse discretization with effective properties is considered at each domain. A zoom-in technique is performed at those domains in which non-linearities take place....

Finite element and b-spline methods for one-dimensional non-local elasticity

Non-local elasticity theories have been intensively applied to a wide range of problems in physics and applied mechanics. Most applications are based either on the integrodifferential constitutive Icm proposed by Eringen or on the gradient constitutive law developed by Aifantis and co-workers. In this work, M>e study a one-dimensional non-local...

A strain gradient approach to the analysis of nanoarches: Formulation and numerical solution with NURBS interpolation

Size effects observed in the mechanical behavior of micro- and nanostructures cannot be modeled by means of classical continuum mechanics. Enhanced continuum models based on nonlocal integro-differential or higher-order differential formulations have shown, on the contrary, that size effect can be modeled when appropriate modifications to the...

On micro-to-macro connections in strong coupling multiscale modeling of softening materials

In this contribution we describe a methodology for the multiscale analysis of heterogeneous quasi-brittle materials. The algorithm is based on the finite element tearing and interconnecting FETI [1] method cast in a non-linear setting. Adaptive multiscale analysis is accounted for with the use of selective refinement at domains that undergo...

Multiscale analysis of heterogeneous brittle materials using domain decomposition techniques

In this contribution we present a multiscale framework for the analysis of brittle materials based on domain decomposition approaches. In particular, the FETI (Finite Element Tearing and Interconnecting) [1] method is selected to solve the decomposed structure. We start our analysis at a coarse level were effective properties are assigned to the...

Applications of domain decomposition techniques for the multiscale modelling of softening materials

In this contribution we describe a methodology for the study of softening brittle materials at different scales of observation. The goal is to account for a higher resolution at those areas that undergo the non-linear processes. We apply the FETI (Finite Element Tearing and Interconnecting) technique to glue different domain resolutions during...

Analysis of intergranular crack propagation in brittle polycrystals with a generalized finite element method and network algorithm

Two different approaches to intergranular crack propagation in brittle polycrystals are contrasted. Crack paths resulting from a method that allows a detailed description of the stress field within a polycrystal are compared to cracks dictated by topological considerations. In the first approach, a fracture path is determined with a Generalized...

Comparison of two novel approaches to model fibre reinforced concrete

We present two approaches to model fibre reinforced concrete. In both approaches, discrete fibre distributions and the behaviour of the fibre-matrix interface are explicitly considered. One approach employs the reaction forces from fibre to matrix while the other is based on the partition of unity finite element method. In none of the methods...

Enhanced domain decomposition techniques for the modeling of softening materials

In this study a FETI: Finite Element Tearing and Interconnecting [1] technique is adopted and exploited for the efficient and accurate modeling of softening materials such as concrete and rock. A fie scale analysis in which concrete is modelled as a three-phase material is used. Special attention is given to the treatment of linear and non...

Multi-scale modeling of softening materials

This paper presents an assessment of a two-scale framework for the study of softening materials. The procedure is based on a hierarchical Finite Element (FE) scheme in which computations are performed both at macro and mesoscopic scale levels. The methodology is chosen specifically to remain valid when the scales are coupled which is frequently...