Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-17T06:13:00.563Z Has data issue: false hasContentIssue false

Effect of Vapor Superheating on Mixed-Convection Film Condensation Along an Isothermal Vertical Cylinder

Published online by Cambridge University Press:  05 May 2011

T.-B. Chang
Affiliation:
Department of Mechanical Engineering, Southern Taiwan University, Tainan, Taiwan 71005, R.O.C.
Get access

Abstract

This paper presents an analytical investigation into the effect of vapor superheating on the mixed-convection of a condensate layer flowing along the outside surface of an isothermal vertical cylinder. The governing system of partial differential equations is transformed into a dimensionless form using the nonsimilar transformation method. In investigating the heat transfer characteristics within the condensate layer and vapor phase, the analysis takes account of both the inertia effects and the convection effects within the condensate layer and the shear resistance at the liquid-vapor interface. The numerical results reveal that vapor superheating has a negligible effect on the temperature profile and local Nusselt number within the condensate layer. Moreover, it is found that a higher forced-flow intensity increases the temperature gradient in the vapor phase, but has a marginal effect on the temperature profile in the condensate layer. Finally, it is shown that the velocity at the liquid-vapor interface increases as the intensity of the forced-flow increases or as the ratio of the condensate layer viscosity to the vapor phase viscosity reduces.

Type
Technical Note
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Nusselt, W., “Die Oberflachen Kondensation des Wasserdampes,” Zeitsehrift des Vereines Deutscher Ingenieure, 60, pp. 541546 (1916).Google Scholar
2.Rohsenow, W. M., “Heat Transfer and Temperature Distribution in Laminar Film Condensation,” Trans. ASME, Journal of Heat Transfer, 78, pp. 16451648 (1956).Google Scholar
3.Sparrow, E. M. and Gregg, J. L., “Laminar Condensation Condensation Heat Transfer on a Horizontal Cylinder,” Trans. ASME, Journal of Heat Transfer, 81, pp. 291296 (1959).CrossRefGoogle Scholar
4.Minkowycz, W. J. and Sparrow, E. M., “Condensation Heat Transfer in the Presence of Noncondensables, Interfacial Resistance, Superheating, Variable Properties, and Diffusion,” International Journal of Heat and Mass Transfer, 6, pp. 11251144 (1966).CrossRefGoogle Scholar
5.Minkowycz, W. J. and Sparrow, E. M., “The Effect of Superheating on Condensation Heat Tranfer in a Forced Convection Boundary Layer Flow,” International Journal of Heat and Mass Transfer, 12, pp. 147154(1969).CrossRefGoogle Scholar
6.Fujii, T., Theory of Laminar Film Condesation, 1st Ed., Springer-Verlag, Chaps. 1–5, New York (1991).Google Scholar
7.Jacobs, H. R., “An Integral Treatment of Combined Body Force and Forced Convection in Laminar Film Condensation,” International Journal of Hat and Mass Transfer, 9, pp. 637648 (1966).Google Scholar
8.Fujii, T. and Uehara, H., “Laminar Filmwise Condesation on a Vertical Surface,” International Journal of Heat and Mass Transfer, 15, pp. 217233 (1972).Google Scholar
9.Lucas, K., “Combined Body Force and Forced Convection in Laminar Film Condensation of Mixed Vapours — Integral and Finite Difference Treatment,” International Journal of Heat and Mass Transfer, 19, pp. 12731280 (1976).CrossRefGoogle Scholar
10.Shu, J. and Wilks, G., “Mixed-Convection Laminar Film Condensation on a Semi-Infinite Vertical Plate,” Journal of Fluid Mechanic, 300, pp. 207229 (1995).CrossRefGoogle Scholar
11.Shu, J. and Wilks, G., “An Accurate Numerical Method for Systems of Convection Differential-Integral Equations Associated with Multiphase Flow,” Computers and Fluids, 24, pp. 625652 (1995).CrossRefGoogle Scholar
12.Winkler, C. M., Chen, T. S. and Minkowycz, W. J., “Film Condensation of Saturated and Superheated Vapors Along Isothermal Vertical Surfaces in Mixed Convection,” Numerical Heat Transfer, Part A, 36, pp. 375393 (1999).Google Scholar
13.Winkler, C. M. and Chen, T. S., “Mixed Convection in Film Condensation From Isothermal Vertical Surfaces-The Entire Regime,” International Journal of Heat and Mass Transfer, 43, pp. 32453251 (2000).Google Scholar
14.Chang, T. B., “Mixed-Convection Film Condensation Along Outside Surface of Vertical Tube in Saturated Vapor with Forced Flow,” Applied Thermal Engineering, 28, pp. 547555 (2008).CrossRefGoogle Scholar
15.Chen, T. S., “Parabolic Systems: Local Nonsimilarity Method,” Handbook of Numerical Heat Transfer, Minkowycz, W. J., Eds., John Wiley and Sons, pp. 183214, New York (1988).Google Scholar
16.Holman, J. P., Heat Transfer, 9th Ed., McGraw-Hill, New York, p. 606 (2002).Google Scholar