A multiscale network method for twophase flow in porous media
Abstract
Porenetwork models of porous media are useful in the study of porescale flow in porous media. In order to extract macroscopic properties from flow simulations in porenetworks, it is crucial the networks are large enough to be considered representative elementary volumes. However, existing twophase network flow solvers are limited to relatively small domains. For this purpose, a multiscale porenetwork (MSPN) method, which takes into account flowrate effects and can simulate larger domains compared to existing methods, was developed. In our solution algorithm, a large pore network is partitioned into several smaller subnetworks. The algorithm to advance the fluid interfaces within each subnetwork consists of three steps. First, a global pressure problem on the network is solved approximately using the multiscale finite volume (MSFV) method. Next, the fluxes across the subnetworks are computed. Lastly, using fluxes as boundary conditions, a dynamic twophase flow solver is used to advance the solution in time. Simulation results of drainage scenarios at different capillary numbers and unfavourable viscosity ratios are presented and used to validate the MSPN method against solutions obtained by an existing dynamic network flow solver.
 Authors:
 Publication Date:
 OSTI Identifier:
 22622312
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics; Journal Volume: 342; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALGORITHMS; APPROXIMATIONS; BOUNDARY CONDITIONS; CAPILLARIES; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; FLOW RATE; FLUIDS; INTERFACES; MATHEMATICAL SOLUTIONS; PARTITION; POROUS MATERIALS; SOLUTIONS; TWOPHASE FLOW; VISCOSITY
Citation Formats
Khayrat, Karim, Email: khayratk@ifd.mavt.ethz.ch, and Jenny, Patrick. A multiscale network method for twophase flow in porous media. United States: N. p., 2017.
Web. doi:10.1016/J.JCP.2017.04.023.
Khayrat, Karim, Email: khayratk@ifd.mavt.ethz.ch, & Jenny, Patrick. A multiscale network method for twophase flow in porous media. United States. doi:10.1016/J.JCP.2017.04.023.
Khayrat, Karim, Email: khayratk@ifd.mavt.ethz.ch, and Jenny, Patrick. 2017.
"A multiscale network method for twophase flow in porous media". United States.
doi:10.1016/J.JCP.2017.04.023.
@article{osti_22622312,
title = {A multiscale network method for twophase flow in porous media},
author = {Khayrat, Karim, Email: khayratk@ifd.mavt.ethz.ch and Jenny, Patrick},
abstractNote = {Porenetwork models of porous media are useful in the study of porescale flow in porous media. In order to extract macroscopic properties from flow simulations in porenetworks, it is crucial the networks are large enough to be considered representative elementary volumes. However, existing twophase network flow solvers are limited to relatively small domains. For this purpose, a multiscale porenetwork (MSPN) method, which takes into account flowrate effects and can simulate larger domains compared to existing methods, was developed. In our solution algorithm, a large pore network is partitioned into several smaller subnetworks. The algorithm to advance the fluid interfaces within each subnetwork consists of three steps. First, a global pressure problem on the network is solved approximately using the multiscale finite volume (MSFV) method. Next, the fluxes across the subnetworks are computed. Lastly, using fluxes as boundary conditions, a dynamic twophase flow solver is used to advance the solution in time. Simulation results of drainage scenarios at different capillary numbers and unfavourable viscosity ratios are presented and used to validate the MSPN method against solutions obtained by an existing dynamic network flow solver.},
doi = {10.1016/J.JCP.2017.04.023},
journal = {Journal of Computational Physics},
number = ,
volume = 342,
place = {United States},
year = 2017,
month = 8
}

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