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Purpose This paper aims to introduce a multiscale computational method for structural failure analysis with inheriting simulation of moving trans-scale boundary (MTB). This method is motivated from the error in domain bridging caused by cross-scale damage evolution, which is common in structural failure induced by damage accumulation.Design/methodology/approach Within the method, vulnerable regions with high stress level are described by continuum damage mechanics, while elastic structural theory is sufficient for the rest, dividing the structural model into two scale domains. The two domains are bridged to generate mixed dimensional finite element equation of the whole system. Inheriting simulation is developed to make the computation of MTB sustainable.Findings Numerical tests of a notched three-point bending beam and a steel frame show that this MTB method can improve efficiency and ensure accuracy while capturing the effect of material damage on deterioration of components and structure.Originality/value The proposed MTB method with inheriting simulation is an extension of multiscale simulation to structural failure analysis. Most importantly, it can deal with cross-scale damage evolution and improve computation efficiency significantly. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to investigate the transient three-dimensional temperature distribution for a laser sintered duraform fine polyamide part by a moving Gaussian laser beam. The primary objective of the present paper is to develop computationally efficient numerical simulation technique with the commercially available finite element software domain for the accurate prediction of the temperature history and heat-affected zones of the laser sintered parts so as to finally obtain the density of the sintered sample. Design/methodology/approach - The paper proposes a mathematical model of scanning by moving laser beam and sintering sub-model. Based on the mathematical models, a simulation model was developed by using author written subroutines in ANSYS® 11.0, a general purpose finite element software. The simulation model was then run at experimental designed points using two-level factorial design of experiments (DOE) approach. The data thus generated were used to predict the equation for the density of sintered part in terms of process parameters using Design Expert software in order to analyse the designed experiments. Findings - Laser power and scan spacing were found to be significant parameters affecting the part density. Amongst the interaction terms, significant effect of laser power was found on the part density at the lower settings of the scan velocity. Temperature-time plots were generated to study the transient temperature distribution for the sintering process and with further applicability to study the thermal stresses. Research limitations/implications - The simulation model hence developed can be used for only simple part geometries and cannot be generalised for any complex geometry. Originality/value - The paper presents a simulation model which is integrated with a DOE approach so as to develop a robust as well as simple and fast approach for the optimization of quality objective. [ABSTRACT FROM AUTHOR]

Purpose – Numerical solution of Plateau’s problem of minimal surface using non-variational finite element method. The paper aims to discuss this issue. Design/methodology/approach – An efficient algorithm is proposed for the computation of minimal surfaces and numerical results are presented. Findings – The solutions obtained here are examined for different cases of non-linearity and are found sufficiently accurate. Originality/value – The manuscript provide the non-variational solution for Plateau’s problem. Thus it has a good value in engineering application. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to extend the bridge scale method (BSM) developed for granular materials with only the solid phase to that taking into account the effects of wetting process in porous continuum. The granular material is modeled as partially saturated porous Cosserat continuum and discrete particle assembly in the coarse and fine scales, respectively. Design/methodology/approach – Based on the mass and momentum conservation laws for the three phases, i.e. the solid skeleton, the pore water and the pore air, the governing equations for the unsaturated porous Biot-Cosserat continuum model in the coarse scale are derived. In light of the passive air pressure assumption, a reduced finite element model for the model is proposed. According to the decoupling of the fine and coarse scale calculations in the BSM, the unsaturated porous Cosserat continuum model using the finite element method and the discrete element model using the discrete element method for granular media are combined. Findings – The numerical results for a 2D example problem of slope stability subjected to increasing rainfall along with mechanical loading demonstrate the applicability and performance of the present BSM. The microscopic mechanisms of macroscopic shear band developed in the slope are demonstrated. Research limitations/implications – Do not account for yet the effects of unsaturated pore water in the fine scale. Originality/value – The novel BSM that couples the Biot-Cosserat porous continuum modeling and the discrete particle assembly modeling in both coarse and fine scales, respectively, is proposed to provide a micro-macro discrete-continuum two-scale modeling approach for numerical simulations of the hydro-mechanical coupling problems in unsaturated granular materials. [ABSTRACT FROM AUTHOR]