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Dynamic Pore-scale Reservoir-condition Imaging of Reaction in Carbonates Using Synchrotron Fast Tomography
Published on: February 21, 2017
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Phase transitions in porous media.
Chiara Gavioli1, Pavel Krejčí2
1Institute of Analysis and Scientific Computing, TU Wien, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria.
Nonlinear Differential Equations and Applications : Nodea
|October 3, 2022
Summary
This study models water diffusion, freezing, and melting in porous solids using a quasistatic thermomechanical system. Researchers proved a global solution exists for this complex system, enhancing our understanding of material behavior under phase change.
Area of Science:
- Geophysics
- Continuum Mechanics
- Materials Science
Background:
- Understanding thermomechanical processes in porous media is crucial for various engineering applications.
- Modeling phase changes (freezing/melting) and hysteresis in water-porous solid interactions presents significant challenges.
Purpose of the Study:
- To analyze a quasistatic thermomechanical system of partial differential equations (PDEs) for water diffusion in porous solids.
- To incorporate the Preisach hysteresis operator for pressure-saturation relations.
- To investigate the existence of global solutions for the coupled system.
Main Methods:
- Development of a comprehensive thermomechanical model for porous solids.
- Application of the Preisach hysteresis operator to describe pressure-saturation behavior.
- Mathematical analysis to prove the existence of global solutions for the system of PDEs.
Main Results:
- A detailed study of the quasistatic thermomechanical system governing water diffusion, freezing, and melting.
- Successful integration of the Preisach hysteresis operator into the model.
- Proof of the existence of a global solution under general data assumptions.
Conclusions:
- The developed model provides a robust framework for studying thermomechanical phenomena in porous materials with phase changes.
- The mathematical analysis confirms the well-posedness of the system, supporting its practical applicability.
- This work advances the understanding of coupled hydro-mechanical-thermal processes in porous media.
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