Showing papers in "Computer Methods in Applied Mechanics and Engineering in 2018"

TL;DR: In this article, a hybrid data-driven method is proposed to capture the multiscale hydro-mechanical coupling effect of porous media with pores of various different sizes, where data driven models generated from supervised machine learning are hybridized with classical constitutive laws in a directed graph that represents the numerical models.

TL;DR: In this paper, a phase field modeling framework for hydrogen assisted cracking is presented, based on a coupled mechanical and hydrogen diffusion response, driven by chemical potential gradients, and a hydrogen-dependent fracture energy degradation law grounded on first principles calculations.

TL;DR: The methodology extends the recently proposed design methodology for a single flexoelectric material and adopts the multi-phase vector level set (LS) model which easily copes with various numbers of phases, efficiently satisfies multiple constraints and intrinsically avoids overlap or vacuum among different phases.

TL;DR: A non-intrusive reduced basis (RB) method is proposed for parametrized nonlinear structural analysis undergoing large deformations and with elasto-plastic constitutive relations, and the Gaussian process regression is used to approximate the projection coefficients.

TL;DR: In this article, sensitivity analysis has been applied to identify the key input parameters influencing the energy conversion factor (ECF) of flexoelectric materials, and the sensitivity of the model output to each of the input parameters at different aspect ratios of the beam is quantified by three various common methods, i.e., Morris One-At-a-Time (MOAT), PCE-Sobol', and Extended Fourier amplitude sensitivity test (EFAST).

TL;DR: An adaptive algorithm is presented which allows to transform FEM nodes into peridynamic nodes and equips standard FEM with the capability to effectively and efficiently describe 3D problems with crack propagation phenomena.

TL;DR: In this article, the authors proposed a constraint energy minimization to construct multiscale spaces for GMsFEM, which is performed in the oversampling domain, which can handle non-decaying components of the local minimizers.

TL;DR: In this article, an extension of the phase-field cohesive zone model for static fracture to dynamic fracture in brittle and quasi-brittle solids is presented, and the model performance is tested with several benchmarks for dynamic brittle and cohesive fracture.

TL;DR: In this paper, the authors derive a phase-field formulation for fracture in elastic-plastic materials as a balance law of microforce, in a new way that honors the dissipative nature of the fracturing processes.

TL;DR: In this article, a fast and viable approach for taking into account turbulence in topology optimization of complex fluid flow systems, without resorting to any simplifying assumptions in the derivation of discrete adjoints, is presented.

TL;DR: In this paper, a methodology is presented for optimal polyhedral description of 3D polycrystals from experimental properties, which is achieved by determining, by optimization, appropriate attributes of the seeds of Laguerre tessellations.

TL;DR: In this article, the authors propose a phase-field/gradient damage model to model complex fracture phenomena where different damaging mechanisms are involved, which can be tailored to many situations where different fracture mechanisms are present as well as model anisotropic fracture phenomena.

TL;DR: In this paper, a mixed-mode I/II fracture model that employs multiple critical energy release rates based on Shen and Stephansson, IJRMMS, 1993 is reformulated in a regularized phase field fracture framework.

TL;DR: The novel concurrent design for cellular structures consisting of multiple patches of material microstructures using a level set-based topological shape optimization method is focused on.

TL;DR: In this paper, a level set method is proposed to solve minimum stress and stress-constrained shape and topology optimization problems, where a p-norm stress functional is used to aggregate stresses in a single constraint.

TL;DR: In this paper, a hierarchical multi-scale formulation is developed to account for both the auxetic behavior of the microstructure and the stiffness of the macrostructure, and a level set method is applied to evolve the shape and topology for each layer.

TL;DR: This work presents original work combining a NURBS-based inverse analysis with both kinematic and constitutive nonlinearities to recover the applied loads and deformations of thin shell structures to show good performance and applicability to computer-aided manufacturing of shell structures.

TL;DR: In this paper, a geometrically regularized gradient-damage model with energetic equivalence for cracking evolution is proposed for modeling localized failure in solids, which is applied to several benchmark tests of concrete under mode I and mixed-mode failure.

TL;DR: Compared to the approximation of the whole limit-state surface, the proposed method only approximates the projection outlines on the limit- state surface, and therefore few DoE are needed to build a high quality metamodel.

TL;DR: A Moving Morphable Void (MMV)-based approach to stress-constrained topology optimization that provides the possibility of obtaining optimized designs with crisp and explicitly parameterized boundaries using much fewer numbers of degrees of freedom for finite element analysis and design variables for optimization, respectively.

TL;DR: In this article, a stable micro-damage homogenization algorithm is presented which removes the material instability issues in the microstructure with representative volume elements (RVE) that are not sensitive to size when computing the homogenized stress-strain response.

TL;DR: A comparison between the empirical performance of the selected sampling methods applied to three numerical examples, including high-order PCE’s, high-dimensional problems, and low oversampling ratios, is presented to provide a road map for practitioners seeking the most suitable sampling technique for a problem at hand.

TL;DR: A multiscale finite element method (MsFEM) is coupled with hybrid phase field method to simulate brittle fracture problems and leads to a significant reduction in the memory and CPU time.

TL;DR: This work proposes an evolutionary topology optimization method for stress minimization design using the bi-directional evolutionary structural optimization (BESO) method, which has been shown efficient, practical and easy-to-implement through a series of 2D and 3D benchmark designs.

TL;DR: This paper addresses a novel aspect in the concurrent optimization of lattice infill and design-dependent movable features, on which boundary conditions are prescribed, and applies the proposed methodology to the concurrent Optimization of cooling channels.

TL;DR: In this paper, a non-uniform rational B-spline (NURBS) based finite element method is used to study the large amplitude free vibration response of the graphene reinforced composite plates in thermal environment.

TL;DR: A rigorous variational-based framework for the phase-field modeling of brittle fracture in elastic solids undergoing small strains is proposed and an incremental minimization principle is introduced, with a novel construction of the stabilization density for the coupled multi-field problem.

TL;DR: The top-down sampling method is introduced that allows to model non-stationary and continuous (but not differentiable) spatial variations of uncertainty sources by creating nested random fields (RFs) where the hyperparameters of an ensemble of RFs is characterized by yet another RF.

TL;DR: An integrated framework of exact modeling, isogeometric analysis and optimization for variable-stiffness panels is developed for the global optimum, and the proposed method is able to provide a more efficient optimum design with significant less computational cost compared to other traditional methods.

TL;DR: The approach is based on the concept of Data Driven Computational Mechanics recently introduced by Kirchdoerfer and Ortiz and builds a database of strain–stress couples that sample the mechanical response of the material for the range of measured strains.