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Title: Studies on dispersive stabilization of porous media flows

Abstract

Motivated by a need to improve the performance of chemical enhanced oil recovery (EOR) processes, we investigate dispersive effects on the linear stability of three-layer porous media flow models of EOR for two different types of interfaces: permeable and impermeable interfaces. Results presented are relevant for the design of smarter interfaces in the available parameter space of capillary number, Peclet number, longitudinal and transverse dispersion, and the viscous profile of the middle layer. The stabilization capacity of each of these two interfaces is explored numerically and conditions for complete dispersive stabilization are identified for each of these two types of interfaces. Key results obtained are (i) three-layer porous media flows with permeable interfaces can be almost completely stabilized by diffusion if the optimal viscous profile is chosen, (ii) flows with impermeable interfaces can also be almost completely stabilized for short time, but become more unstable at later times because diffusion flattens out the basic viscous profile, (iii) diffusion stabilizes short waves more than long waves which leads to a “turning point” Peclet number at which short and long waves have the same growth rate, and (iv) mechanical dispersion further stabilizes flows with permeable interfaces but in some cases has amore » destabilizing effect for flows with impermeable interfaces, which is a surprising result. These results are then used to give a comparison of the two types of interfaces. It is found that for most values of the flow parameters, permeable interfaces suppress flow instability more than impermeable interfaces.« less

Authors:
;  [1]
  1. Department of Mathematics, Texas A&M University, College Station, Texas 77843 (United States)
Publication Date:
OSTI Identifier:
22598899
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Fluids; Journal Volume: 28; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 42 ENGINEERING; CAPILLARIES; COMPARATIVE EVALUATIONS; DIFFUSION; FLOW MODELS; INSTABILITY; INTERFACES; LAYERS; POROUS MATERIALS; STABILIZATION

Citation Formats

Daripa, Prabir, E-mail: prabir.daripa@math.tamu.edu, and Gin, Craig. Studies on dispersive stabilization of porous media flows. United States: N. p., 2016. Web. doi:10.1063/1.4961162.
Daripa, Prabir, E-mail: prabir.daripa@math.tamu.edu, & Gin, Craig. Studies on dispersive stabilization of porous media flows. United States. doi:10.1063/1.4961162.
Daripa, Prabir, E-mail: prabir.daripa@math.tamu.edu, and Gin, Craig. 2016. "Studies on dispersive stabilization of porous media flows". United States. doi:10.1063/1.4961162.
@article{osti_22598899,
title = {Studies on dispersive stabilization of porous media flows},
author = {Daripa, Prabir, E-mail: prabir.daripa@math.tamu.edu and Gin, Craig},
abstractNote = {Motivated by a need to improve the performance of chemical enhanced oil recovery (EOR) processes, we investigate dispersive effects on the linear stability of three-layer porous media flow models of EOR for two different types of interfaces: permeable and impermeable interfaces. Results presented are relevant for the design of smarter interfaces in the available parameter space of capillary number, Peclet number, longitudinal and transverse dispersion, and the viscous profile of the middle layer. The stabilization capacity of each of these two interfaces is explored numerically and conditions for complete dispersive stabilization are identified for each of these two types of interfaces. Key results obtained are (i) three-layer porous media flows with permeable interfaces can be almost completely stabilized by diffusion if the optimal viscous profile is chosen, (ii) flows with impermeable interfaces can also be almost completely stabilized for short time, but become more unstable at later times because diffusion flattens out the basic viscous profile, (iii) diffusion stabilizes short waves more than long waves which leads to a “turning point” Peclet number at which short and long waves have the same growth rate, and (iv) mechanical dispersion further stabilizes flows with permeable interfaces but in some cases has a destabilizing effect for flows with impermeable interfaces, which is a surprising result. These results are then used to give a comparison of the two types of interfaces. It is found that for most values of the flow parameters, permeable interfaces suppress flow instability more than impermeable interfaces.},
doi = {10.1063/1.4961162},
journal = {Physics of Fluids},
number = 8,
volume = 28,
place = {United States},
year = 2016,
month = 8
}
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