Numerical modeling of multiphase flows in microchannels
The present work devises and implements numerical procedures to simulate multiphase flows where precise prediction of these interfaces is essential. A three-phase flow model with two fluids and a solid phase involving two moving interfaces, i.e. fluid-fluid (F-F) and fluid-solid (F-S) interfaces, is...
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sg-ntu-dr.10356-52742023-03-11T17:43:15Z Numerical modeling of multiphase flows in microchannels Yap, Yit Fatt Zhang Hengyun Chai Chee Kiong, John School of Mechanical and Aerospace Engineering DRNTU::Engineering::Mechanical engineering::Fluid mechanics The present work devises and implements numerical procedures to simulate multiphase flows where precise prediction of these interfaces is essential. A three-phase flow model with two fluids and a solid phase involving two moving interfaces, i.e. fluid-fluid (F-F) and fluid-solid (F-S) interfaces, is proposed. Two limiting cases of the model are two-fluid flow and fluid-solid flow. The F-F interface is captured using a level-set method. Two mass conservation schemes, i.e. Global (GMC) and Local (LMC) Mass Correction Schemes, are presented to ensure mass conservation. While GMC is for general two-fluid flow problems, LMC is developed for stratified two-fluid flows. Artificial viscosity is introduced in selected region away from the F-F interface during the advection of the level-set function and shown to improve numerical stability. A new fixed-grid F-S interface tracking technique is proposed. Solids, represented by local distance functions, are tracked explicitly. The procedure can handle flows with multiple complex shaped solids. The F-F interface tracking procedure is extended to the case where there is a slip velocity at the solid surfaces as encountered in the modeling of electrophoresis of particles. A set of combined conservation equations is employed for the physical domain consists of the three phases. Surface tension effects at the F-F interface, both curvature and Marangoni driven, are incorporated using the Continuum Surface Force model. Solution of the governing equations together with the F-F interface capturing and F-S interface tracking procedures are implemented in a finite volume method. Validation of the present model is made against available results in two-fluid and fluid-solid flows. The applications of the present model in a large variety of multiphase flow problems are demonstrated. DOCTOR OF PHILOSOPHY (MAE) 2008-09-17T10:46:50Z 2008-09-17T10:46:50Z 2007 2007 Thesis Yap, Y. F. (2007). Numerical modeling of multiphase flows in microchannels. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/5274 10.32657/10356/5274 Nanyang Technological University application/pdf |
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DRNTU::Engineering::Mechanical engineering::Fluid mechanics Yap, Yit Fatt Numerical modeling of multiphase flows in microchannels |
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The present work devises and implements numerical procedures to simulate multiphase flows where precise prediction of these interfaces is essential. A three-phase flow model with two fluids and a solid phase involving two moving interfaces, i.e. fluid-fluid (F-F) and fluid-solid (F-S) interfaces, is proposed. Two limiting cases of the model are two-fluid flow and fluid-solid flow. The F-F interface is captured using a level-set method. Two mass conservation schemes, i.e. Global (GMC) and Local (LMC) Mass Correction Schemes, are presented to ensure mass conservation. While GMC is for general two-fluid flow problems, LMC is developed for stratified two-fluid flows. Artificial viscosity is introduced in selected region away from the F-F interface during the advection of the level-set function and shown to improve numerical stability. A new fixed-grid F-S interface tracking technique is proposed. Solids, represented by local distance functions, are tracked explicitly. The procedure can handle flows with multiple complex shaped solids. The F-F interface tracking procedure is extended to the case where there is a slip velocity at the solid surfaces as encountered in the modeling of electrophoresis of particles. A set of combined conservation equations is employed for the physical domain consists of the three phases. Surface tension effects at the F-F interface, both curvature and Marangoni driven, are incorporated using the Continuum Surface Force model. Solution of the governing equations together with the F-F interface capturing and F-S interface tracking procedures are implemented in a finite volume method. Validation of the present model is made against available results in two-fluid and fluid-solid flows. The applications of the present model in a large variety of multiphase flow problems are demonstrated. |
author2 |
Zhang Hengyun |
author_facet |
Zhang Hengyun Yap, Yit Fatt |
format |
Theses and Dissertations |
author |
Yap, Yit Fatt |
author_sort |
Yap, Yit Fatt |
title |
Numerical modeling of multiphase flows in microchannels |
title_short |
Numerical modeling of multiphase flows in microchannels |
title_full |
Numerical modeling of multiphase flows in microchannels |
title_fullStr |
Numerical modeling of multiphase flows in microchannels |
title_full_unstemmed |
Numerical modeling of multiphase flows in microchannels |
title_sort |
numerical modeling of multiphase flows in microchannels |
publishDate |
2008 |
url |
https://hdl.handle.net/10356/5274 |
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1761781419403640832 |