A Coupled Thermo-Hydro-Mechanical Model for Capturing Frost Heave Under Chilled Gas Pipelines

2020 ◽  
Author(s):  
SeonHong Na ◽  
Mahyar Malekzade Kebria ◽  
Kshama Roy
Keyword(s):  
Porous Media ◽  
Pore Water ◽  
Constitutive Models ◽  
Thermal Characteristics ◽  
Mixture Theory ◽  
Melting Process ◽  
Ice Crystal ◽  
Gas Pipelines ◽  
Computational Framework ◽  
Darcy Flux

Abstract This paper presents a thermo-hydro-mechanics theory and corresponding computational framework to capture the freezethaw action of frozen porous media and associated frost action under chilled gas pipelines. Based on the mixture theory, frost-susceptible soils are formulated to capture the Darcy flux and thermal actions below the pipelines. Constitutive models that combine the cryo-suction are presented to reproduce the changes in volume, strength, and thermal characteristics of solid grain, pore water, and ice crystal. A generalized hardening rule is adopted to replicate the elasto-plastic responses which strengthens the frozen porous media due to ice crystallization. Changes in permeability and thermal diffusivity are also incorporated by considering the phase transitions of pore water and ice crystal. Numerical examples for pipeline applications are designed to analyze the influence of the freezing and melting process around the pipelines.

PORE-SCALE SIMULATION OF ICE MELTING PROCESS IN POROUS MEDIA

2017 ◽  
Author(s):  
Pu He ◽  
Li Chen ◽  
Yu-Tong Mu ◽  
Wen-Quan Tao
Keyword(s):  
Porous Media ◽  
Melting Process ◽  
Pore Scale ◽  
Ice Melting

scholarly journals A computational framework to establish data-driven constitutive models for time- or path-dependent heterogeneous solids

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Weijian Ge ◽  
Vito L. Tagarielli
Keyword(s):  
Constitutive Models ◽  
Computational Procedure ◽  
Data Driven ◽  
Dissipated Energy ◽  
Computational Framework ◽  
Heterogeneous Solids ◽  
Non Linear ◽  
Recorded Data ◽  
Path Dependent ◽  
Computational Homogenisation

AbstractWe propose and implement a computational procedure to establish data-driven surrogate constitutive models for heterogeneous materials. We study the multiaxial response of non-linear n-phase composites via Finite Element (FE) simulations and computational homogenisation. Pseudo-random, multiaxial, non-proportional histories of macroscopic strain are imposed on volume elements of n-phase composites, subject to periodic boundary conditions, and the corresponding histories of macroscopic stresses and plastically dissipated energy are recorded. The recorded data is used to train surrogate, phenomenological constitutive models based on neural networks (NNs), and the accuracy of these models is assessed and discussed. We analyse heterogeneous composites with hyperelastic, viscoelastic or elastic–plastic local constitutive descriptions. In each of these three cases, we propose and assess optimal choices of inputs and outputs for the surrogate models and strategies for their training. We find that the proposed computational procedure can capture accurately and effectively the response of non-linear n-phase composites subject to arbitrary mechanical loading.

scholarly journals A Review of Mixture Theory for Deformable Porous Media and Applications

2017 ◽  
Vol 7 (9) ◽  
pp. 917 ◽  
Author(s):  
Javed Siddique ◽  
Aftab Ahmed ◽  
Asim Aziz ◽  
Chaudry Khalique
Keyword(s):  
Porous Media ◽  
Mixture Theory ◽  
Deformable Porous Media

scholarly journals Modeling chemical reactions in porous media: a review

2021 ◽  
Vol 33 (6) ◽  
pp. 2279-2300
Author(s):  
Bettina Detmann
Keyword(s):  
Porous Media ◽  
Chemical Reactions ◽  
Chemical Potential ◽  
Mixture Theory ◽  
Reaction Diffusion ◽  
Second Law Of Thermodynamics ◽  
Reaction Diffusion Equations ◽  
Set Up ◽  
The 1960S ◽  
In The Beginning

AbstractFirst, different porous media theories are presented. Some approaches are based on the classical mixture theory for fluids introduced in the 1960s by Truesdell and Coworkers. One of the first researchers who extended the theory to porous media (thus mixtures containing at least one solid constituent) and also accounting for chemical reactions was Bowen. Another important branch of porous media theory goes back to Biot. In the beginning, he dealt with classical geotechnical problems and set up his model empirically. Mathematicians often use reaction–diffusion equations which are limited in comparison with continuum models by several restrictive assumptions and very often only applicable to special problems. In this paper, the focus lies on approaches based on the mixture theory which incorporate chemical reactions. Different strategies to describe the chemical potential for mixtures are presented, and different opinions about the exploitation of the second law of thermodynamics for mixtures are put forward. Finally, several works of different types including chemical reactions in porous media are summarized.

From mixture theory to biot’s approach for porous media

1998 ◽  
Vol 35 (34-35) ◽  
pp. 4619-4635 ◽  
Author(s):  
Olivier Coussy ◽  
Luc Dormieux ◽  
Emmanuel Detournay
Keyword(s):  
Porous Media ◽  
Mixture Theory

Experimental and numerical investigation of microparticle transport and deposition in the context of permafrost thaw

2021 ◽  
Author(s):  
Madiha Khadhraoui ◽  
John Molson ◽  
Najat Bhiry
Keyword(s):  
Porous Media ◽  
Pore Water ◽  
Water Velocity ◽  
Kinetic Term ◽  
Column Experiments ◽  
Order Kinetic ◽  
Permafrost Degradation ◽  
Pore Water Velocity ◽  
Laboratory Column ◽  
Study Laboratory

<p>In natural porous environments, soil particle migration during flow plays an important role in soil stability and pollutant transport by affecting soil mechanical properties and water quality. In northern areas, permafrost degradation alters the subsurface connection pathways leading to mass movements and rearrangement of the soil. To date, few models have included the influence of temporal and spatial variations of flow velocity and porous media heterogeneity on the transport and deposition of suspended particles.</p><p>In this study, laboratory column experiments and a numerical model were used to investigate these issues. The laboratory column experiments were carried out under different flow rates and the effect of porous media heterogeneity was investigated using different grain size distributions. The soil columns were reconstituted from several samples taken in the studied site, the Tasiapik Valley, located in the discontinuous permafrost zone near Umiujaq, Nunavik, Québec. During the experiments, the spatio-temporal distribution of the porosity and the hydraulic conductivity was monitored using X-ray computed tomography imaging (CT-SCAN). Using the pore water velocity computed from the groundwater flow solution, the advection–dispersion transport equation with a first-order kinetic term for particle deposition was solved using the finite element model Heatflow/Smoker. The dependency of the attachment kinetics on the pore water velocity and on the porous media heterogeneity was included. The model was tested and validated with an analytical solution and calibrated with the experimental data. Our simulations highlight the roles of hydrodynamic conditions and soil characteristics on particle transport and deposition mechanisms and the susceptibility of the porous medium to thermo-suffosion in permafrost environments.</p>

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