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You searched for subject:(Heterogeneous capillary pressure). Showing records 1 – 3 of 3 total matches.

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University of Texas – Austin

1. Saadatpoor, Ehsan, 1982-. Local capillary trapping in geological carbon storage.

Degree: PhD, Petroleum Engineering, 2012, University of Texas – Austin

After the injection of CO₂ into a subsurface formation, various storage mechanisms help immobilize the CO₂. Injection strategies that promote the buoyant movement of CO₂ during the post-injection period can increase immobilization by the mechanisms of dissolution and residual phase trapping. In this work, we argue that the heterogeneity intrinsic to sedimentary rocks gives rise to another category of trapping, which we call local capillary trapping. In a heterogeneous storage formation where capillary entry pressure of the rock is correlated with other petrophysical properties, numerous local capillary barriers exist and can trap rising CO₂ below them. The size of barriers depends on the correlation length, i.e., the characteristic size of regions having similar values of capillary entry pressure. This dissertation evaluates the dynamics of the local capillary trapping and its effectiveness to add an element of increased capacity and containment security in carbon storage in heterogeneous permeable media. The overall objective is to obtain the rigorous assessment of the amount and extent of local capillary trapping expected to occur in typical storage formations. A series of detailed numerical simulations are used to quantify the amount of local capillary trapping and to study the effect of local capillary barriers on CO₂ leakage from the storage formation. Also, a research code is developed for finding clusters of local capillary trapping from capillary entry pressure field based on the assumption that in post-injection period the viscous forces are negligible and the process is governed solely by capillary forces. The code is used to make a quantitative assessment of an upper bound for local capillary trapping capacity in heterogeneous domains using the geologic data, which is especially useful for field projects since it is very fast compared to flow simulation. The results show that capillary heterogeneity decreases the threshold capacity for non-leakable storage of CO₂. However, in cases where the injected volume is more than threshold capacity, capillary heterogeneity adds an element of security to the structural seal, regardless of how CO₂ is accumulated under the seal, either by injection or by buoyancy. In other words, ignoring heterogeneity gives the worst-case estimate of the risk. Nevertheless, during a potential leakage through failed seals, a range of CO₂ leakage amounts may occur depending on heterogeneity and the location of the leak. In geologic CO₂ storage in typical saline aquifers, the local capillary trapping can result in large volumes that are sufficiently trapped and immobilized. In fact, this behavior has significant implications for estimates of permanence of storage, for assessments of leakage rates, and for predicting ultimate consequences of leakage. Advisors/Committee Members: Bryant, Steven L. (advisor), Sepehrnoori, Kamy, 1951- (advisor).

Subjects/Keywords: CO₂; Geological carbon storage; Capillary pressure; Heterogeneous; Scaling; Local capillary trapping; Leakage; Upscaling

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APA (6th Edition):

Saadatpoor, Ehsan, 1. (2012). Local capillary trapping in geological carbon storage. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/18490

Chicago Manual of Style (16th Edition):

Saadatpoor, Ehsan, 1982-. “Local capillary trapping in geological carbon storage.” 2012. Doctoral Dissertation, University of Texas – Austin. Accessed April 19, 2021. http://hdl.handle.net/2152/18490.

MLA Handbook (7th Edition):

Saadatpoor, Ehsan, 1982-. “Local capillary trapping in geological carbon storage.” 2012. Web. 19 Apr 2021.

Vancouver:

Saadatpoor, Ehsan 1. Local capillary trapping in geological carbon storage. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2012. [cited 2021 Apr 19]. Available from: http://hdl.handle.net/2152/18490.

Council of Science Editors:

Saadatpoor, Ehsan 1. Local capillary trapping in geological carbon storage. [Doctoral Dissertation]. University of Texas – Austin; 2012. Available from: http://hdl.handle.net/2152/18490


University of Texas – Austin

2. -5063-5889. Numerical analysis of multiphase flows in porous media on non-rectangular geometry.

Degree: PhD, Computational Science, Engineering, and Mathematics, 2017, University of Texas – Austin

Fluid flow through porous media is a subject of common interest in many branches of engineering as well as applied natural science. In this work, we investigate the behavior and numerical treatment of multiphase flow in porous media. To be more specific, we take the sequestration of CO₂ in geological media as an example. Mathematical modeling and numerical study of carbon sequestration helps to predict both short and long-term behavior of CO₂ storage in geological media, which can be a benefit in many ways. This work aims at developing accurate and efficient numerical treatment for problems in porous media on non-rectangular geometries. Numerical treatment of Darcy flow and transport have been developed for many years on rectangular and simplical meshes. However, extra effort is required to extend them to general non-rectangular meshes. In this dissertation work, for flow simulation, we develop new H(div)- conforming mixed finite elements (AT and AT [superscript red] ) which are accurate on cuboidal hexahedra. We also develop the new direct serendipity finite element (DS [subscript r] ), which is H¹ -conforming and accurate on quadrilaterals and a special family of hexahedra called truncated cubes. The use of the direct serendipity finite element reduces the number of degrees of freedom significantly and therefore accelerates numerical simulations. For transport, we use the newly developed direct serendipity elements in an enriched Galerkin method (EG), which is locally conservative. The entropy viscosity stabilization is applied to eliminate spurious oscillations. We test the EG-DS [subscript r] method on problems with diffusion, transport, and coupled flow and transport. Finally, we study two-phase flow in heterogeneous porous media with capillary pressure. We work on a new formulation of the problem and force the continuity of the capillary flux with a modification to conquer the degeneracy. The numerical simulation of two-phase flow is conducted on non-rectangular grids and uses the new elements. Advisors/Committee Members: Arbogast, Todd James, 1957- (advisor), Wheeler, Mary F (committee member), Ghattas, Omar (committee member), Demkowicz, Leszek F (committee member), Hesse, Marc A (committee member).

Subjects/Keywords: Multiphase flow; Porous media; Mixed finite element; H(div)-approximation; Arbogast-Tao element; Arbogast-Correa element; Direct serendipity element; Serendipity element; Enriched Galerkin method; Entropy viscosity stabilization; Capillary flux reconstruction; Heterogeneous capillary pressure; Two-phase flow

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APA (6th Edition):

-5063-5889. (2017). Numerical analysis of multiphase flows in porous media on non-rectangular geometry. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/68171

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Chicago Manual of Style (16th Edition):

-5063-5889. “Numerical analysis of multiphase flows in porous media on non-rectangular geometry.” 2017. Doctoral Dissertation, University of Texas – Austin. Accessed April 19, 2021. http://hdl.handle.net/2152/68171.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7th Edition):

-5063-5889. “Numerical analysis of multiphase flows in porous media on non-rectangular geometry.” 2017. Web. 19 Apr 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-5063-5889. Numerical analysis of multiphase flows in porous media on non-rectangular geometry. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2017. [cited 2021 Apr 19]. Available from: http://hdl.handle.net/2152/68171.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-5063-5889. Numerical analysis of multiphase flows in porous media on non-rectangular geometry. [Doctoral Dissertation]. University of Texas – Austin; 2017. Available from: http://hdl.handle.net/2152/68171

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

3. Dutta, Sourav. Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery.

Degree: PhD, Mathematics, 2017, Texas A&M University

We study multiphase, multicomponent flow of incompressible fluids through porous media. Such flows are of vital interest in various applied science and engineering disciplines like geomechanics, groundwater flow and soil-remediation, construction engineering, hydrogeology, biology and biophysics, manufacturing of polymer composites, reservoir engineering, etc. In particular, we study chemical Enhanced Oil Recovery (EOR) techniques like polymer and surfactant-polymer (SP) flooding in two space dimensions. We develop a mathematical model for incompressible, immiscible, multicomponent, two-phase porous media flow by introducing a new global pressure function in the context of SP flooding. This model consists of a system of flow equations that incorporates the effect of capillary pressure and also the effect of polymer and surfactant on viscosity, interfacial tension and relative permeabilities of the two phases. We propose a hybrid method to solve the coupled system of equations for global pressure, water saturation, polymer concentration and surfactant concentration in which the elliptic global pressure equation is solved using a discontinuous finite element method and the transport equations for water saturation and concentrations of the components are solved by a Modified Method Of Characteristics (MMOC) in the multicomponent setting. We also prove convergence of the hybrid method by assuming an optimal O(h) order estimate for the gradient of the pressure obtained using the discontinuous finite element method and using this estimate to analyze the convergence of the MMOC method for the transport system. The novelty in this proof is the convergence analysis of the MMOC procedure for a nonlinear system of transport equations as opposed to previous results which have only considered a single transport equation. For this purpose, we consider an analogous single-component system of transport equations and discuss the possibility of extending the analysis to multicomponent systems. We obtain error estimates for the transport variables and these estimates are validated numerically in two ways. Firstly, we compare them with numerical error estimates obtained using an exact solution. Secondly, we also compare these estimates with results obtained from realistic numerical simulations of flows arising in enhanced oil recovery processes. This mathematical model and hybrid numerical procedure have been successfully applied to solve a variety of configurations representing different chemical flooding processes arising in EOR. We perform numerical simulations to validate the method and to demonstrate its robustness and efficiency in capturing the details of the various underlying physical and numerical phenomena. We introduce a new technique to test for the influence of grid alignment on the numerical results and apply this technique on the hybrid method to show that the grid orientation effect is negligible. We perform simulations using different types of heterogeneous permeability field data which include piecewise… Advisors/Committee Members: Daripa, Prabir (advisor), Howard, Peter (committee member), King, Michael J (committee member), Kuchment, Peter (committee member), Lazarov, Raytcho (committee member).

Subjects/Keywords: Surfactant-polymer flooding; Multicomponent two-phase flow; Global pressure; Capillary pressure; Finite Element Method; Modified Method of Characteristics; Convergence analysis; Error estimates; Numerical simulations; Heterogeneous permeability

…use of surfactant further improves oil recovery by reducing the capillary pressure between… …characteristic associated with multiphase flows in porous media known as the capillary pressure. At the… …turn, determines the contact angle which is used to define capillary pressure pc at the pore… …scale. Intuitively, capillary pressure can be understood as the excess pressure that the non… …This notion allows us to define capillary pressure in terms of the macroscopic field… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Dutta, S. (2017). Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/165997

Chicago Manual of Style (16th Edition):

Dutta, Sourav. “Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery.” 2017. Doctoral Dissertation, Texas A&M University. Accessed April 19, 2021. http://hdl.handle.net/1969.1/165997.

MLA Handbook (7th Edition):

Dutta, Sourav. “Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery.” 2017. Web. 19 Apr 2021.

Vancouver:

Dutta S. Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Apr 19]. Available from: http://hdl.handle.net/1969.1/165997.

Council of Science Editors:

Dutta S. Mathematical Models and Numerical Methods for Porous Media Flows Arising in Chemical Enhanced Oil Recovery. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/165997

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