OS0606 Comparison of Meso-Scale modeling and Macro-Scale modeling for draping simulation

AbstractThe COVID-19 pandemic has kept the world in suspense for the past months. In most federal countries such as Germany, locally varying conditions demand for state- or county-level decisions. However, this requires a deep understanding of the meso-scale outbreak dynamics between micro-scale agent models and macro-scale global models. Here, we introduce a reparameterized SIQRD network model that accounts for local political decisions to predict the spatio-temporal evolution of the pandemic in Germany at county and city resolution. Our optimized model reproduces state-wise cumulative infections and deaths as reported by the Robert-Koch Institute, and predicts development for individual counties at convincing accuracy. We demonstrate the dominating effect of local infection seeds, and identify effective measures to attenuate the rapid spread. Our model has great potential to support decision makers on a state and community politics level to individually strategize their best way forward.

Download Full-text

A Multi-Scale Modeling Approach for Simulating Crack Sensing in Polymer Fibrous Composites Using Electrically Conductive Carbon Nanotube Networks. Part II: Meso- and Macro-Scale Analyses

Aerospace ◽

10.3390/aerospace5040106 ◽

2018 ◽

Vol 5 (4) ◽

pp. 106 ◽

Cited By ~ 6

Author(s):

Konstantinos Tserpes ◽

Christos Kora

Keyword(s):

Carbon Nanotube ◽

Fibrous Composites ◽

Electrically Conductive ◽

Micro Scale ◽

Multi Scale ◽

Modeling Approach ◽

Scale Modeling ◽

Macro Scale ◽

Multi Scale Modeling ◽

Meso Scale

This is the second of a two-paper series describing a multi-scale modeling approach developed to simulate crack sensing in polymer fibrous composites by exploiting interruption of electrically conductive carbon nanotube (CNT) networks. The approach is based on the finite element (FE) method. Numerical models at three different scales, namely the micro-scale, the meso-scale and the macro-scale, have been developed using the ANSYS APDL environment. In the present paper, the meso- and macro-scale analyses are described. In the meso-scale, a two-dimensional model of the CNT/polymer matrix reinforced by carbon fibers is used to develop a crack sensing methodology from a parametric study which relates the crack position and length with the reduction of current flow. In the meso-model, the effective electrical conductivity of the CNT/polymer computed from the micro-scale is used as input. In the macro-scale, the final implementation of the crack sensing methodology is performed on a CNT/polymer/carbon fiber composite volume using as input the electrical response of the cracked CNT/polymer derived at the micro-scale and the crack sensing methodology. Analyses have been performed for cracks of two different lengths. In both cases, the numerical model predicts with good accuracy both the length and position of the crack. These results highlight the prospect of conductive CNT networks to be used as a localized structural health monitoring technique.

Download Full-text

A Multi-Scale Modeling Approach for Simulating Crack Sensing in Polymer Fibrous Composites Using Electrically Conductive Carbon Nanotube Networks. Part II: Meso- and Macro-Scale Analyses

10.20944/preprints201808.0456.v1 ◽

2018 ◽

Author(s):

Konstantinos Tserpes ◽

Christos Kora

Keyword(s):

Carbon Nanotube ◽

Fibrous Composites ◽

Electrically Conductive ◽

Micro Scale ◽

Multi Scale ◽

Modeling Approach ◽

Scale Modeling ◽

Macro Scale ◽

Multi Scale Modeling ◽

Meso Scale

This is the second of a two-paper series describing a multi-scale modeling approach developed to simulate crack sensing in polymer fibrous composites by exploiting interruption of electrically conductive carbon nanotube (CNT) networks. The approach is based on the finite element (FE) method. FE models at three different scales, namely the micro-scale, the meso-scale and the macro-scale, have been developed using the ANSYS PDL environment. In the present paper, the meso- and macro-scale analyses are described. In the meso-scale, a two-dimensional model of the CNT/polymer matrix reinforced by carbon fibers is used to develop a crack sensing methodology from a parametric study which relates the crack position and length with the reduction of current flow. In the meso-model, the effective electrical conductivity of the CNT/polymer computed from the micro-scale is used as input. In the macro-scale, the final implementation of the crack sensing methodology is performed on a CNT/polymer/carbon fiber composite volume using as input the electrical response of the cracked CNT/polymer derived at the micro-scale and the crack sensing methodology. Analyses have been performed for cracks of two different lengths. In both cases, the numerical model predicts with good accuracy both the length and position of the crack. These results highlight the prospect of conductive CNT networks to be used as a localized structural health monitoring technique.

Download Full-text

Meso-Scale Experimental & Numerical Studies for Predicting Macro-scale Performance of Advanced Reactive Materials (ARMs)

10.21236/ada623037 ◽

2015 ◽

Author(s):

Naresh Thadhani ◽

Arun Gokhale ◽

Jason Quenneville ◽

Jennifer Breidenich ◽

Manny Gonzales ◽

...

Keyword(s):

Reactive Materials ◽

Numerical Studies ◽

Macro Scale ◽

Meso Scale

Download Full-text

A novel synergistic multi-scale modeling framework to predict micro- and meso-scale damage behaviors of 2D triaxially braided composite

International Journal of Damage Mechanics ◽

10.1177/10567895211033974 ◽

2021 ◽

pp. 105678952110339

Author(s):

Hongyong Jiang ◽

Yiru Ren ◽

Qiduo Jin

Keyword(s):

Compressive Load ◽

Scale Model ◽

Modeling Framework ◽

Braided Composite ◽

Multi Scale ◽

Scale Modeling ◽

Bridge Model ◽

Multi Scale Modeling ◽

Transverse Damage ◽

Meso Scale

A novel synergistic multi-scale modeling framework with a coupling of micro- and meso-scale is proposed to predict damage behaviors of 2D-triaxially braided composite (2DTBC). Based on the Bridge model, the internal stress and micro damage of constituent materials are respectively coupled with the stress and damage of tow. The initial effective elastic properties of tow (IEEP) used as the predefined data are estimated by micro-mechanics models. Due to in-situ effects, stress concentration factor (SCF) is considered in the micro matrix, exhibiting progressive damage accumulation. Comparisons of IEEP and strengths between the Bridge and Chamis’ theory are conducted to validate the values of IEEP and SCF. Based on the representative volume element (RVE), the macro properties and damage modes of 2DTBC are predicted to be consistent with available experiments and meso-scale simulation. Both axial and transverse damage mechanisms of 2DTBC under tensile or compressive load are revealed. Micro fiber and matrix damage accumulations have significant effects on the meso-scale axial and transverse damage of tows due to multi-scale coupling effects. Different from existing meso-/multi-scale models, the proposed multi-scale model can capture a crucial phenomenon that the transverse damage of tow is vulnerable to micro fiber fracture. The proposed multi-scale framework provides a robust tool for future systematic studies on constituent materials level to larger-scale aeronautical materials.

Download Full-text

Permeability Prediction in the Impregnation Stage of Resin Transfer Moulding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.1211 ◽

2010 ◽

Vol 160-162 ◽

pp. 1211-1216

Author(s):

Zhuang Liu ◽

Xiao Qing Wu

Keyword(s):

Stokes Equations ◽

Approximate Model ◽

Local Deformation ◽

Resin Transfer Moulding ◽

Moulding Process ◽

2D Simulation ◽

Macro Scale ◽

Darcy Equations ◽

Transfer Moulding ◽

Meso Scale

The impregnation stage of the Resin Transfer Moulding process can be simulated by solving the Darcy equations on a mould model, with a ‘macro-scale’ finite element method. For every element, a local ‘meso-scale’ permeability must be determined, taking into account the local deformation of the textile reinforcement. This paper demonstrates that the meso-scale permeability can be computed efficiently and accurately by using meso-scale simulation tools. We discuss the speed and accuracy requirements dictated by the macro-scale simulations. We show that these requirements can be achieved for two meso-scale simulators, coupled with a geometrical textile reinforcement modeller. The first solver is based on a finite difference discretisation of the Stokes equations, the second uses an approximate model, based on a 2D simulation of the flow.

Download Full-text

Axial meso-scale modeling of gas-liquid-solid fluidized beds

Chemical Engineering Science ◽

10.1016/j.ces.2018.11.005 ◽

2019 ◽

Vol 196 ◽

pp. 188-201 ◽

Cited By ~ 2

Author(s):

Yongli Ma ◽

Mingyan Liu ◽

Yuan Zhang

Keyword(s):

Fluidized Beds ◽

Scale Modeling ◽

Meso Scale

Download Full-text

Distinct structure-function relationships across cortical regions and connectivity scales in the rat brain

10.1101/742833 ◽

2019 ◽

Author(s):

Milou Straathof ◽

Michel R.T. Sinke ◽

Theresia J.M. Roelofs ◽

Erwin L.A. Blezer ◽

R. Angela Sarabdjitsingh ◽

...

Keyword(s):

Functional Connectivity ◽

Structure Function ◽

Rat Brain ◽

Resting State ◽

Structural Connectivity ◽

Distinct Structure ◽

Macro Scale ◽

Function Relationship ◽

The Brain ◽

Meso Scale

AbstractAn improved understanding of the structure-function relationship in the brain is necessary to know to what degree structural connectivity underpins abnormal functional connectivity seen in many disorders. We integrated high-field resting-state fMRI-based functional connectivity with high-resolution macro-scale diffusion-based and meso-scale neuronal tracer-based structural connectivity, to obtain an accurate depiction of the structure-function relationship in the rat brain. Our main goal was to identify to what extent structural and functional connectivity strengths are correlated, macro- and meso-scopically, across the cortex. Correlation analyses revealed a positive correspondence between functional connectivity and macro-scale diffusion-based structural connectivity, but no correspondence between functional connectivity and meso-scale neuronal tracer-based structural connectivity. Locally, strong functional connectivity was found in two well-known resting-state networks: the sensorimotor and default mode network. Strong functional connectivity within these networks coincided with strong short-range intrahemispheric structural connectivity, but with weak heterotopic interhemispheric and long-range intrahemispheric structural connectivity. Our study indicates the importance of combining measures of connectivity at distinct hierarchical levels to accurately determine connectivity across networks in the healthy and diseased brain. Distinct structure-function relationships across the brain can explain the organization of networks and may underlie variations in the impact of structural damage on functional networks and behavior.

Download Full-text

Energy Dissipation During Prey Capture Process in Spider Orb Webs

Journal of Applied Mechanics ◽

10.1115/1.4047364 ◽

2020 ◽

Vol 87 (9) ◽

Author(s):

Yanhui Jiang ◽

Hamid Nayeb-Hashemi

Keyword(s):

Energy Dissipation ◽

Significant Role ◽

Prey Capture ◽

Aerodynamic Drag ◽

Material Damping ◽

Capture Process ◽

Spider Dragline Silk ◽

Multi Scale ◽

Scale Modeling ◽

Macro Scale

Abstract Capture of a prey by spider orb webs is a dynamic process with energy dissipation. The dynamic response of spider orb webs under prey impact requires a multi-scale modeling by considering the material microstructures and the assembly of spider silks in the macro-scale. To better understand the prey capture process, this paper addresses a multi-scale approach to uncover the underlying energy dissipation mechanisms. Simulation results show that the microstructures of spider dragline silk play a significant role on energy absorption during prey capture. The alteration of the microstructures, material internal friction, and plastic deformation lead to energy dissipation, which is called material damping. In addition to the material damping in the micro-scale modeling, the energy dissipation due to drag force on the prey is also taken into consideration in the macro-scale modeling. The results indicate that aerodynamic drag, i.e., aero-damping, plays a significant role when the prey size is larger than a critical size.

Download Full-text