scholarly journals A unified modelling and simulation for coupled anomalous transport in porous media and its finite element implementation

2021 ◽  
Author(s):  
O. Barrera
Keyword(s):  
Finite Element ◽  
Porous Media ◽  
Diffusion Equation ◽  
Pore Pressure ◽  
Large Scale ◽  
Anomalous Transport ◽  
Computational Framework ◽  
Transient Phenomena ◽  
Large Scale Structures ◽  
Pressure Diffusion

AbstractThis paper presents an unified mathematical and computational framework for mechanics-coupled “anomalous” transport phenomena in porous media. The anomalous diffusion is mainly due to variable fluid flow rates caused by spatially and temporally varying permeability. This type of behaviour is described by a fractional pore pressure diffusion equation. The diffusion transient phenomena is significantly affected by the order of the fractional operators. In order to solve 3D consolidation problems of large scale structures, the fractional pore pressure diffusion equation is implemented in a finite element framework adopting the discretised formulation of fractional derivatives given by Grunwald–Letnikov (GL). Here the fractional pore pressure diffusion equation is implemented in the commercial software Abaqus through an open-source UMATHT subroutine. The similarity between pore pressure, heat and hydrogen transport is also discussed in order to show that it is possible to use the coupled thermal-stress analysis to solve fractional consolidation problems.

The MPS Reconstruction of Porous Media Using Multiple-Grid Templates

2013 ◽  
Vol 462-463 ◽  
pp. 462-465 ◽  
Author(s):  
Yi Du ◽  
Ting Zhang
Keyword(s):  
Porous Media ◽  
Large Scale ◽  
Grid Method ◽  
Training Image ◽  
Multiple Point ◽  
Grid Data ◽  
Large Scale Structures ◽  
Complex Features ◽  
Grid Nodes ◽  
Data Template

It is difficult to reconstruct the unknown information only by some sparse known data in the reconstruction of porous media. Multiple-point geostatistics (MPS) has been proved to be a powerful tool to capture curvilinear structures or complex features in training images. One solution to capture large-scale structures while considering a data template with a reasonably small number of grid nodes is provided by the multiple-grid method. This method consists in scanning a training image using increasingly finer multiple-grid data templates instead of a big and dense data template. The experimental results demonstrate that multiple-grid data templates and MPS are practical in porous media reconstruction.

scholarly journals Propagation of pore pressure diffusion waves in saturated porous media

2015 ◽  
Vol 117 (13) ◽  
pp. 134902 ◽  
Author(s):  
Duoxing Yang ◽  
Qi Li ◽  
Lianzhong Zhang
Keyword(s):  
Porous Media ◽  
Pore Pressure ◽  
Saturated Porous Media ◽  
Diffusion Waves ◽  
Pressure Diffusion

A Meta-Modeling Procedure for Updating the Finite Element Model of an Arch Bridge Model

2013 ◽  
Vol 540 ◽  
pp. 79-86
Author(s):  
De Jun Wang ◽  
Yang Liu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Dynamic Analysis ◽  
Large Scale ◽  
Model Updating ◽  
Element Model ◽  
Fe Model ◽  
Large Scale Structures ◽  
Bridge Model ◽  
Scale Structures

Finite element (FE) model updating of structures using vibration test data has received considerable attentions in recent years due to its crucial role in fields ranging from establishing a reality-consistent structural model for dynamic analysis and control, to providing baseline model for damage identification in structural health monitoring. Model updating is to correct the analytical finite element model using test data to produce a refined one that better predict the dynamic behavior of structure. However, for real complex structures, conventional updating methods is difficult to be utilized to update the FE model of structures due to the heavy computational burden for the dynamic analysis. Meta-model is an effective surrogate model for dynamic analysis of large-scale structures. An updating method based on the combination between meta-model and component mode synthesis (CMS) is proposed to improve the efficiency of model updating of large-scale structures. The effectiveness of the proposed method is then validated by updating a scaled suspender arch bridge model using the simulated data.

Application of Multi-Criteria Optimization to Large-Scale Structures Design

2014 ◽  
Vol 693 ◽  
pp. 171-176
Author(s):  
Milan Sága ◽  
Peter Pecháč ◽  
Lenka Jakubovičová
Keyword(s):  
Finite Element ◽  
Optimal Design ◽  
Objective Function ◽  
Optimization Algorithm ◽  
Large Scale ◽  
Finite Element Analyses ◽  
Large Scale Structures ◽  
Whole Process ◽  
Deformation Stability ◽  
Scale Structures

The paper presents fundamental principles and application of the large-scale truss structure PKP25-20i optimal design based on a multi-criteria optimization algorithm. The multi-objective function contains conditions for deformation, stability and cumulative damage obtained by finite element analyses. The whole process was implemented and realized in special Matlab’s procedures and FEM software Cosmos/M.

Sensitivity-Based Finite Element Model Updating Using Dynamic Condensation Approach

2018 ◽  
Vol 18 (08) ◽  
pp. 1840004 ◽  
Author(s):  
Tianyi Zhu ◽  
Wei Tian ◽  
Shun Weng ◽  
Hanbin Ge ◽  
Yong Xia ◽  
...  
Keyword(s):  
Finite Element ◽  
Optimization Design ◽  
Large Scale ◽  
Model Updating ◽  
Element Model ◽  
Fe Model ◽  
Large Scale Structures ◽  
Dynamic Condensation ◽  
Scale Structures ◽  
Fe Model Updating

An accurate finite element (FE) model is frequently used in damage detection, optimization design, reliability analysis, nonlinear analysis, and so forth. The FE model updating of large-scale structures is usually time-consuming or even impossible. This paper proposes a dynamic condensation approach for model updating of large-scale structures. The eigensolutions are calculated from a condensed eigenequation and the eigensensitivities are calculated without selection of additional master DOFs, which is helpful to improve the efficiency of FE model updating. The proposed model updating method is applied to an eight-storey frame and the Jun Shan Yangtze Bridge. By employing the dynamic condensation approach, the number of iterations for the eigensensitivities is gradually increased according to the model updating process, which contributes to accelerate the convergence of model updating.

scholarly journals Numerical Simulation on Hydromechanical Coupling in Porous Media Adopting Three-Dimensional Pore-Scale Model

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Jianjun Liu ◽  
Rui Song ◽  
Mengmeng Cui
Keyword(s):  
Finite Element ◽  
Porous Media ◽  
Pore Pressure ◽  
Three Dimensional ◽  
Confining Pressure ◽  
Scale Model ◽  
Micro Ct ◽  
Pore Scale ◽  
Hydromechanical Coupling ◽  
Rock Matrix

A novel approach of simulating hydromechanical coupling in pore-scale models of porous media is presented in this paper. Parameters of the sandstone samples, such as the stress-strain curve, Poisson’s ratio, and permeability under different pore pressure and confining pressure, are tested in laboratory scale. The micro-CT scanner is employed to scan the samples for three-dimensional images, as input to construct the model. Accordingly, four physical models possessing the same pore and rock matrix characteristics as the natural sandstones are developed. Based on the micro-CT images, the three-dimensional finite element models of both rock matrix and pore space are established by MIMICS and ICEM software platform. Navier-Stokes equation and elastic constitutive equation are used as the mathematical model for simulation. A hydromechanical coupling analysis in pore-scale finite element model of porous media is simulated by ANSYS and CFX software. Hereby, permeability of sandstone samples under different pore pressure and confining pressure has been predicted. The simulation results agree well with the benchmark data. Through reproducing its stress state underground, the prediction accuracy of the porous rock permeability in pore-scale simulation is promoted. Consequently, the effects of pore pressure and confining pressure on permeability are revealed from the microscopic view.

Sign in / Sign up

Export Citation Format

Share Document