Two-phase non-equilibrium models: the challenge of improving phase change heat transfer prediction
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In this article, a detailed qualitative description of the classical heat transfer coefficient behaviour is presented together with two examples of departure from macroscopic equilibrium largely supported by experimental evidence, as well as successful attempts to model the non-equilibrium phase change phenomena taking place in the two situations.Abstract:
This lecture addresses some recent developments in modelling of macroscopic thermodynamic and hydrodynamic non-equilibrium phenomena in convective phase change (boiling and condensation) of pure fluids and mixtures. Proper accounting of such phenomena may hold the key to explain and predict deviations from the classical (equilibrium) phase change convective heat transfer behaviour reported in the literature and yet not fully understood. In the first part of the paper, a detailed qualitative description of the classical heat transfer coefficient behaviour is presented together with two examples of departure from macroscopic equilibrium largely supported by experimental evidence. The second part of the paper reviews successful attempts to model the non-equilibrium phase change phenomena taking place in the two situations. The first example is a thermodynamic non-equilibrium slug flow model (one in which saturated Taylor bubbles become separated by slugs of subcooled liquid) that predicts the peaks in heat transfer coefficient at near-zero thermodynamic quality observed in forced convective boiling of some pure liquids. The occurrence of such peaks is typical of low latent heat, low thermal conductivity systems and of systems in which the vapour volume formation rate for a given heat flux is large. The second example is a comprehensive annular flow calculation methodology that predicts the decrease in the heat transfer coefficient with increasing quality observed in convective boiling of binary and multicomponent mixtures. In this case, as will be seen, coupled mass transfer resistance and hydrodynamic non-equilibrium effects generate concentration gradients between the liquid film and entrained droplets that are responsible for the heat transfer deterioration. In addition, it will be shown that for condensation of mixtures the methodology predicts a heat transfer intensification which has been subsequently confirmed by independent experimental results.read more
Citations
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Heat transfer—A review of 2005 literature
Richard J Goldstein,W. E. Ibele,Suhas V. Patankar,Terrence W. Simon,Thomas H. Kuehn,Paul J Strykowski,Kumar K. Tamma,Joachim Heberlein,Jane H. Davidson,John C. Bischof,Francis A Kulacki,Uwe Kortshagen,Sean C. Garrick,Vinod Srinivasan,Kalyanjit Ghosh,Rajat Mittal +15 more
TL;DR: A review of the heat transfer literature published in 2005 can be found in this article, where the authors restrict themselves to papers published in English through a peer-review process, with selected translations from journals published in other languages.
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Development of Gas-Liquid Slug Flow Measurement Using Continuous-Wave Doppler Ultrasound and Bandpass Power Spectral Density
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References
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Book
Convective boiling and condensation
John G. Collier,John R. Thome +1 more
TL;DR: In this paper, the basic models of two-phase flow are discussed and empirical treatments of two phase flow are provided. But the authors focus on convective boiling and condensing.
Journal ArticleDOI
New method for prediction of binary gas-phase diffusion coefficients
Book
Multicomponent mass transfer
Ross Taylor,Rajamani Krishna +1 more
TL;DR: In this paper, the authors present an important book on multicomponent mass transfer, meant for readers already acquainted with the theory of mass transfer and the fundamentals of transport phenomena, and provide a computer diskette with the book; the examples in Chapters 1--13 are solvable using this diskette and the commercial package Mathcad which the user must obtain.