Ensemble phase averaging equations for multiphase flows in porous media, part I: the bundleoftubes model
Abstract
A bundleoftubes construct is used as a model system to study ensemble averaged equations for multiphase flow in a porous material. Momentum equations for the fluid phases obtained from the method are similar to Darcy's law, but with additional terms. We study properties of the additional terms, and the conditions under which the averaged equations can be approximated by the diffusion model or the extended Darcy's law as often used in models for multiphase flows in porous media. Although the bundleoftubes model is perhaps the simplest model for a porous material, the ensemble averaged equation technique developed in this paper assumes the very same form in more general treatments described in Part 2 of the present work (Zhang 2009). Any model equation system intended for the more general cases must be understood and tested first using simple models. The concept of ensemble phase averaging is dissected here in physical terms, without involved mathematics through its application to the idealized bundleoftubes model for multiphase flow in porous media.
 Authors:
 Los Alamos National Laboratory
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 956632
 Report Number(s):
 LAUR0807866; LAUR087866
Journal ID: ISSN 03019322; IJMFBP; TRN: US201016%%2317
 DOE Contract Number:
 AC5206NA25396
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: International Journal of Multiphase Flow
 Country of Publication:
 United States
 Language:
 English
 Subject:
 36; DIFFUSION; EQUATIONS; FLUIDS; MULTIPHASE FLOW; POROUS MATERIALS; SIMULATION
Citation Formats
Yang, Dali, Zhang, Duan, and Currier, Robert. Ensemble phase averaging equations for multiphase flows in porous media, part I: the bundleoftubes model. United States: N. p., 2008.
Web.
Yang, Dali, Zhang, Duan, & Currier, Robert. Ensemble phase averaging equations for multiphase flows in porous media, part I: the bundleoftubes model. United States.
Yang, Dali, Zhang, Duan, and Currier, Robert. 2008.
"Ensemble phase averaging equations for multiphase flows in porous media, part I: the bundleoftubes model". United States.
doi:. https://www.osti.gov/servlets/purl/956632.
@article{osti_956632,
title = {Ensemble phase averaging equations for multiphase flows in porous media, part I: the bundleoftubes model},
author = {Yang, Dali and Zhang, Duan and Currier, Robert},
abstractNote = {A bundleoftubes construct is used as a model system to study ensemble averaged equations for multiphase flow in a porous material. Momentum equations for the fluid phases obtained from the method are similar to Darcy's law, but with additional terms. We study properties of the additional terms, and the conditions under which the averaged equations can be approximated by the diffusion model or the extended Darcy's law as often used in models for multiphase flows in porous media. Although the bundleoftubes model is perhaps the simplest model for a porous material, the ensemble averaged equation technique developed in this paper assumes the very same form in more general treatments described in Part 2 of the present work (Zhang 2009). Any model equation system intended for the more general cases must be understood and tested first using simple models. The concept of ensemble phase averaging is dissected here in physical terms, without involved mathematics through its application to the idealized bundleoftubes model for multiphase flow in porous media.},
doi = {},
journal = {International Journal of Multiphase Flow},
number = ,
volume = ,
place = {United States},
year = 2008,
month = 1
}

The 48 papers contained in this volume are part of a sixday conference whose technical topics ranged in scope from fundamental applications involving free and forced convection, boiling, radiation, and conduction to applications involving heat exchangers and microscale heat transfer phenomena within electronic circuits. Volume 3 covers experimental studies in multiphase flow, twophase flow, and flow in porous materials, as well as measuring methods. The applications include steam turbines, pipelines, fluidized beds, refrigerating machinery, drying, solidification processes, and cooling systems. Most papers have been processed separately for inclusion on the data base.

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