TY - JOUR

T1 - Variational formulation of stationary two-phase flow distribution

AU - Giannetti, Niccolo

AU - Redo, Mark A.B.

AU - Saito, Kiyoshi

AU - Yoshimura, Hiroaki

N1 - Funding Information:
H.Y. is partially supported by JSPS Grant-in-Aid for Scientific Research ( 17H01097 ) JST CREST (Grant Number JPMJCR1914 ), and Waseda University ( SR 2021C-134 ).
Funding Information:
This paper is based on results obtained from a project commissioned by the New Energy and Industrial Technology Development Organization (NEDO) and is supported by the MEXT Top Global University Project, Waseda University ( SR 2021C-134 ) and the Organization for University Research Initiatives (Evolution and application of energy conversion theory in collaboration with modern mathematics).
Publisher Copyright:
© 2020 Association for Computing Machinery. All rights reserved.

PY - 2021/8

Y1 - 2021/8

N2 - This paper discusses the extremisation of the entropy production in fluidic networks to gain insight into using non-equilibrium thermodynamics for mathematically formulating thermal engineering transfer phenomena. In the study, a variational formulation of the two-phase flow distribution in a fluidic junction is developed. Moreover, based on the flow representation, it is shown that the flow is distributed such that the entropy production rate is either maximised or minimised. Specifically, considering a homogeneous representation of the flow in an adiabatic fluidic network, the flow rates are distributed to maximize the entropy generation rate. Contrarily, when a separate flow representation is adopted, the stationary flow rates are distributed to yield the minimum entropy generation rate. Additionally, various characteristics which affect the flow distribution ratio and phase separation, such as the geometric imbalance, the gravitational static head, the total inlet mass flux, different thermo-physical properties of the fluid, and a generalised number of parallel branches are explored. This supports the possibility of relying on non-equilibrium thermodynamics, instead of introducing case-specific empirical correlations, for obtaining general mathematical formulations of thermal engineering transfer phenomena.

AB - This paper discusses the extremisation of the entropy production in fluidic networks to gain insight into using non-equilibrium thermodynamics for mathematically formulating thermal engineering transfer phenomena. In the study, a variational formulation of the two-phase flow distribution in a fluidic junction is developed. Moreover, based on the flow representation, it is shown that the flow is distributed such that the entropy production rate is either maximised or minimised. Specifically, considering a homogeneous representation of the flow in an adiabatic fluidic network, the flow rates are distributed to maximize the entropy generation rate. Contrarily, when a separate flow representation is adopted, the stationary flow rates are distributed to yield the minimum entropy generation rate. Additionally, various characteristics which affect the flow distribution ratio and phase separation, such as the geometric imbalance, the gravitational static head, the total inlet mass flux, different thermo-physical properties of the fluid, and a generalised number of parallel branches are explored. This supports the possibility of relying on non-equilibrium thermodynamics, instead of introducing case-specific empirical correlations, for obtaining general mathematical formulations of thermal engineering transfer phenomena.

KW - Distribution

KW - Entropy generation

KW - Two-phase flow

KW - Variational formulation

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U2 - 10.1016/j.csite.2021.101082

DO - 10.1016/j.csite.2021.101082

M3 - Article

AN - SCOPUS:85107479812

VL - 26

JO - Case Studies in Thermal Engineering

JF - Case Studies in Thermal Engineering

SN - 2214-157X

M1 - 101082

ER -