scholarly journals A New Model Describing Plastic Distortion Fully Coupled with Ductile Damage

2014 ◽  
Vol 81 ◽  
pp. 1234-1239 ◽  
Author(s):  
Zhenming Yue ◽  
Houssem Badreddine ◽  
Khemais Saanouni
Keyword(s):  
Ductile Damage ◽  
New Model ◽  
Plastic Distortion ◽  
Fully Coupled

scholarly journals An advanced elastoplastic framework accounting for induced plastic anisotropy fully coupled with ductile damage

2021 ◽  
pp. 106620
Author(s):  
J. Paux ◽  
M. Ben Bettaieb ◽  
H. Badreddine ◽  
F. Abed-Meraim ◽  
C. Labergere ◽  
...  
Keyword(s):  
Plastic Anisotropy ◽  
Ductile Damage ◽  
Fully Coupled

Numerical simulation of easy opening lids for food cans using fully coupled advanced constitutives equations with ductile damage

2008 ◽  
Vol 1 (S1) ◽  
pp. 149-152
Author(s):  
C. Labergere ◽  
C. Dubois ◽  
K. Saanouni ◽  
O. Beigneux ◽  
J. J. Li
Keyword(s):  
Numerical Simulation ◽  
Ductile Damage ◽  
Fully Coupled

scholarly journals Explicit silicate cycling in the Kiel Marine Biogeochemistry Model, version 3 (KMBM3) embedded in the UVic ESCM version 2.9

2020 ◽  
Author(s):  
Karin Kvale ◽  
David P. Keller ◽  
Wolfgang Koeve ◽  
Katrin J. Meissner ◽  
Chris Somes ◽  
...  
Keyword(s):  
Southern Ocean ◽  
Primary Production ◽  
Large Scale ◽  
Climate Model ◽  
Net Primary Production ◽  
Coupled Model ◽  
Co2 Concentration ◽  
Ecosystem Model ◽  
New Model ◽  
Fully Coupled

Abstract. We describe and test a new model of biological marine silicate cycling, implemented in the University of Victoria Earth System Climate Model (UVic ESCM) version 2.9. This new model adds diatoms, which are a key aspect of the biological carbon pump, to an existing ecosystem model. The new model performs well against important ocean biogeochemical indicators and captures the large-scale features of the marine silica cycle. Furthermore it is computationally efficient, allowing both fully-coupled, long-timescale transient simulations, as well as "offline" transport matrix spinups. We assess the fully-coupled model against modern ocean observations, the historical record since 1960, and a business-as-usual atmospheric CO2 forcing to the year 2300. The model simulates a global decline in net primary production (NPP) of 1.3 % having occurred since the 1960s, with the strongest declines in the tropics, northern mid-latitudes, and Southern Ocean. The simulated global decline in NPP reverses after the year 2100 (forced by the extended RCP CO2 concentration scenario), and NPP returns to pre-industrial rates by 2300. This recovery is dominated by increasing primary production in the Southern Ocean, mostly by calcifying phytoplankton. Large increases in calcifying phytoplankton in the Southern Ocean offset a decline in the low latitudes, producing a global net calcite export in 2300 that varies only slightly from pre-industrial rates. Diatoms migrate southward in our simulations, following the receding Antarctic ice front, but are out-competed by calcifiers across most of their pre-industrial Southern Ocean habitat. Global opal export production thus drops to 50 % of its pre-industrial value by 2300. Model nutrients phosphate, silicate, and nitrate build up along the Southern Ocean particle export pathway, but dissolved iron (for which ocean sources are held constant) increases in the upper ocean. This different behaviour of iron is attributed to a reduction of low-latitude NPP (and consequently, a reduction in both uptake and export and particle, including calcite, scavenging), an increase in seawater temperatures (raising the solubility of particle forms), and stratification that "traps" the iron near the surface. These results are meant to serve as a baseline for sensitivity assessments to be undertaken with this model in the future.

Enhanced CDM model accounting of stress triaxiality and Lode angle for ductile damage prediction in metal forming

2020 ◽  
pp. 105678952095804
Author(s):  
Kai Zhang ◽  
Houssem Badreddine ◽  
Naila Hfaiedh ◽  
Khemais Saanouni ◽  
Jianlin Liu
Keyword(s):  
Constitutive Equations ◽  
Damage Model ◽  
Stress Triaxiality ◽  
Ductile Damage ◽  
Irreversible Processes ◽  
State Variables ◽  
Damage Prediction ◽  
Proposed Model ◽  
Lode Angle ◽  
Fully Coupled

This paper deals with the prediction of ductile damage based on CDM approach fully coupled with advanced elastoplastic constitutive equations. This fully coupled damage model is developed based on the total energy equivalence assumption under the thermodynamics of irreversible processes framework with state variables. In this model, the damage evolution is enhanced by accounting for both stress triaxiality and Lode angle. The proposed constitutive equations are implemented into Finite Element (FE) code ABAQUS/Explicit through a user material subroutine (VUMAT). The material parameters are determined by the hybrid experimental-numerical method using various tensile and shear tests. Validation of the proposed model has been done using different tests of two aluminum alloys (Al6061-T6 and Al6014-T4). Through comparisons of numerical simulations with experimental results for different loading paths, the predictive capabilities of the proposed model have been shown. The model is found to be able to capture the initiation as well as propagation of macro-crack in sheet and bulk metals during their forming processes.

A new fully-coupled atmospheric-hydrological model for urban areas: development and testing

2021 ◽  
Author(s):  
Mahdad Talebpour ◽  
Claire Welty ◽  
Elie Bou-Zeid
Keyword(s):  
Soil Moisture ◽  
Land Surface ◽  
Urban Areas ◽  
Overland Flow ◽  
Model Output ◽  
Impervious Surfaces ◽  
New Model ◽  
Terrestrial Hydrology ◽  
Rain Events ◽  
Fully Coupled

<p>Urban areas have distinct features (e.g. impervious surfaces) which modify the energy-water balance at the upper subsurface, lower atmosphere, and over the land surface. Moreover, the atmosphere and groundwater are strongly coupled in places with shallow groundwater. To improve the understanding of urban atmospheric-hydrological processes, their interconnections, and their impacts on other environmental processes, a new fully-coupled urban atmosphere-surface-subsurface hydrometeorological model was developed. The new model brings together WRF-PUCM (Princeton Urban Canopy Model) with ParFlow (a 3D variably saturated groundwater model with an integrated 2D overland flow component) to build WRF-PUCM-PF. The new model and the original non-coupled WRF-PUCM were both applied to a small watershed (10.64 km2) in a heavily urbanized area in the Baltimore metropolitan region as a demonstration test case. To capture atmospheric-hydrological processes at scales closer to urban heterogeneous land cover, models were run at a 90-m horizontal resolution using the LES mode in WRF. The analysis period after the two models were spun up to an identical initial condition spanned 96 hours from July 19 to July 23, 2008. The period was selected as it started with a drydown period for 40 hours followed by several intense rain events. This period allowed evaluation of both models' responses to dry-down and rain events. First the models were run with homogeneous similar hydrogelogic input to isolate the effect of terrestrial hydrology implementations in each model. In response to rain events, the homogeneous WRF-PUCM model output gained and retained a 40% greater amount of soil moisture (area-averaged) compared to the homogeneous WRF-PUCM-PF case. WRF-PUCM performed poorly in lateral distribution of water due to its 1D implementation of subsurface hydrology and lack of overland flow parameterization. The spatial distribution of soil moisture at the end of the simulation in a homogeneous WRF-PUCM model looked similar to the cumulative spatial distribution rain at the end of the simulation with no indication of surface topography impact on soil moisture distribution. On the other hand, lateral movement of water in WRF-PUCM-PF resulted in a more realistic distribution of soil moisture following topography. To further analyze the impact of urban areas, results of WRF-PUCM-PF simulations incorporating heterogeneous subsurface hydrogeology  were compared with WRF-PUCM with its 2D implementation of hydrogeology units for the region. The heterogeneous WRF-PUCM model generated a 10-fold greater area-averaged soil moisture increase compared to the heterogeneous WRF-PUCM-PF case. Influenced by lateral hydrology and impervious surfaces, the heterogeneous WRF-PUCM-PF model output, generated lower latent heat flux, resulting in half of the domain having higher land surface temperatures (2-10 ◦C), compared to the heterogeneous WRF-PUCM model. Overall, the new model provides a tool that can enhance simulation of urban areas by combining ParFlow’s representation of terrestrial hydrology, PUCM’s improved representation of the urban heterogeneous energy and water balance, and incorporation of higher-resolution urban heterogeneous microclimatic variations.</p>

On non-associative anisotropic finite plasticity fully coupled with isotropic ductile damage for metal forming

2010 ◽  
Vol 26 (11) ◽  
pp. 1541-1575 ◽  
Author(s):  
Houssem Badreddine ◽  
Khemaïs Saanouni ◽  
Abdelwaheb Dogui
Keyword(s):  
Metal Forming ◽  
Ductile Damage ◽  
Finite Plasticity ◽  
Fully Coupled

Advances in Virtual Metal Forming Including the Ductile Damage Occurrence: Application to 3D Sheet Metal Deep Drawing

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
K. Saanouni ◽  
H. Badreddine ◽  
M. Ajmal
Keyword(s):  
Sheet Metal ◽  
Constitutive Equations ◽  
Deep Drawing ◽  
Metal Forming ◽  
Ductile Damage ◽  
Classical Dynamic ◽  
Damage Initiation ◽  
Integration Schemes ◽  
Local Integration ◽  
Fully Coupled

An advanced numerical methodology to simulate virtually any sheet or bulk metal forming including various kinds of initial and induced anisotropies fully coupled to the isotropic ductile damage is presented. First, the fully coupled anisotropic constitutive equations in the framework of continuum damage mechanics under large plastic deformation are presented. Special care is paid to the strong coupling between the main mechanical fields such as elastoplasticity, mixed nonlinear isotropic and kinematic hardenings, ductile isotropic damage, and contact with friction in the framework of nonassociative and non-normal formulation. The associated numerical aspects concerning both the local integration of the coupled constitutive equations as well as the (global) equilibrium integration schemes are presented. The local integration is outlined, thanks to the Newton iterative scheme applied to a reduced system of ordinary differential equations. For the global resolution of the equilibrium problem, the classical dynamic explicit (DE) scheme with an adaptive time step control is used. This fully coupled procedure is implemented into the general purpose finite element code for metal forming simulation, namely, ABAQUS/EXPLICIT. This gives a powerful numerical tool for virtual optimization of metal forming processes before their physical realization. This optimization with respect to the ductile damage occurrence can be made either to avoid the damage occurrence to have a nondamaged part as in forging, stamping, deep drawing, etc., or to favor the damage initiation and growth for some metal cutting processes as in blanking, guillotining, or machining by chip formation. Two 3D examples concerning the sheet metal forming are given in order to show the capability of the proposed methodology to predict the damage initiation and growth during metal forming processes.

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