Abo Bibliothek: Guest
Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen
Journal of Enhanced Heat Transfer
Impact-faktor: 1.406 5-jähriger Impact-Faktor: 1.075 SJR: 0.287 SNIP: 0.653 CiteScore™: 1.2

ISSN Druckformat: 1065-5131
ISSN Online: 1563-5074

Volumes:
Volumen 27, 2020 Volumen 26, 2019 Volumen 25, 2018 Volumen 24, 2017 Volumen 23, 2016 Volumen 22, 2015 Volumen 21, 2014 Volumen 20, 2013 Volumen 19, 2012 Volumen 18, 2011 Volumen 17, 2010 Volumen 16, 2009 Volumen 15, 2008 Volumen 14, 2007 Volumen 13, 2006 Volumen 12, 2005 Volumen 11, 2004 Volumen 10, 2003 Volumen 9, 2002 Volumen 8, 2001 Volumen 7, 2000 Volumen 6, 1999 Volumen 5, 1998 Volumen 4, 1997 Volumen 3, 1996 Volumen 2, 1995 Volumen 1, 1994

Journal of Enhanced Heat Transfer

DOI: 10.1615/JEnhHeatTransf.v6.i2-4.110
pages 217-236

A Critical Review of Condensation Heat Transfer Predicting Models-Effects of Surface-tension Force

Chien-Yuh Yang
National Central University

ABSTRAKT

Condensation is defined as the transformation of vapor to its liquid state. Gravity and vapor shear are the two forces that drive the flow of the condensate film inside plain tubes. Traditional condensation predicting models generally include the effects of these two forces. For finned tubes, the surface-tension force will also be important. This paper provides a critical review of existed predicting models to correlate condensation heat transfer coefficients. Gravity-force dominated models, vapor-shear dominated models and the effects of surface-tension force are all discussed. Three basic methods have been used to model the vapor-shear dominated annular liquid film. The first model assumed that the vapor core could be replaced with an equivalent liquid flow that would yield the same value for the vapor shear. The second model assumed that the major resistance to heat transfer was offered only by the laminar liquid sublayer. The third model assumed that the velocity in liquid film could be predicted using von Karman universal velocity profile.
Yang and Webb (1997) study shows that at low-mass-velocity and high-vapor-quality conditions, the effect of surface tension is comparable to that of vapor shear for condensation heat transfer inside a micro-fin tube with 13 μm fin tip radius. Owing to the manufacturing technology development of integrated circuits, smaller tubes and fin geometries can be made and used for increasing the condensation heat transfer coefficient. Because the surface-tension drainage force is proportional directly to the inverse of fin-tip radius, the importance of the surface-tension effect will increase with the development of micro-fabrication technology. The Yang and Webb (1997) model is the first model that accounts for the effects of vapor and surface-tension forces simultaneously. However, their database did not cover wide range of fluid properties and fin geometries. More work is needed on correlation and theoretically based models.


Articles with similar content:

Two-Phase Pressure Drop for Condensation inside a Horizontal Tube
ICHMT DIGITAL LIBRARY ONLINE, Vol.19, 1981, issue
R. G. Sardesai, David Butterworth, R. G. Owen
MODELING OF FROST GROWTH ON SURFACES WITH VARYING CONTACT ANGLE
3rd Thermal and Fluids Engineering Conference (TFEC), Vol.11, 2018, issue
Ellyn Harges, Lorenzo Cremaschi
Pure Vapour Condensation of Refrigerants 11 and 113 on a Horizontal Integral Finned Tube at High Vapour Velocity
Journal of Enhanced Heat Transfer, Vol.1, 1994, issue 1
Luisa Rossetto, Giovanni Antonio Longo, B. Bella, Alberto Cavallini
MECHANISTIC MODEL FOR NUCLEATE BOILING CRISIS AT DIFFERENT GRAVITY FIELDS
International Heat Transfer Conference 10, Vol.12, 1994, issue
Victor V. Yagov, Yu. B. Zudin
Effect of Fin Tip Radius for Film Condensation on Micro-fin Surfaces
International Heat Transfer Conference 12, Vol.44, 2002, issue
Chien-Yuh Yang, Fei-Peng Chang, Chih-Feng Fan