Hostname: page-component-84b7d79bbc-l82ql Total loading time: 0 Render date: 2024-07-30T12:42:51.410Z Has data issue: false hasContentIssue false
  • English
  • Français

Film evaporation of a spherical droplet over a hot surface: fluid mechanics and heat/mass transfer analysis

Published online by Cambridge University Press:  26 April 2006

S. Zhang  and
G. Gogos
S. Zhang
Affiliation:
Department of Mechanical and Aerospace Engineering, Rutgers University, P.O. Box 909, Piscatway, NJ 08855-0909, USA
G. Gogos
Affiliation:
Department of Mechanical and Aerospace Engineering, Rutgers University, P.O. Box 909, Piscatway, NJ 08855-0909, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Film evaporation of a spherical droplet over a hot surface is investigated in this paper. In view of the radial evaporation-induced velocity at the liquid-gas interface, an improvement over the classical flow field solution of Stimson & Jeffery (1926) needs to be employed. In addition to the flow, the energy equation internally and externally to the droplet and the species equation in the gas phase are also solved. The boundary conditions at the droplet surface couple the temperature, species and flow field. Analytical expressions for the hydrodynamic force and its components (viscous and pressure) that the droplet experiences are obtained. It is shown that, depending on the droplet separation distance from the hot surface and the type of liquid, there may be a substantial temperature variation along the droplet surface. Furthermore, considering a quasi-steady approximation for the droplet regression rate and balancing at each time step the weight of the droplet with the hydrodynamic force it experiences, time histories are obtained numerically for various quantities of interest. Thus, it is predicted that the droplet moves away from the hot surface while evaporating and that the initially substantial temperature variation along the droplet surface decreases with time and diminishes towards the end of the droplet lifetime. It is also shown that the droplet surface temperature is more uniform at higher hot-surface temperature.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 222 , January 1991 , pp. 543 - 563
Copyright
© 1991 Cambridge University Press

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

Avedisian, C. T., Ioffredo, C. & O'Connor, M. J. 1984 Film boiling of discrete droplets of mixtures of coal and water on a horizontal brass surface. Chem. Engng Sci. 39, 319–327.Google Scholar
Avedisian, C. T. & Koplik, J., 1987 Leidenfrost boiling of methanol droplets on hot porous/ceramic surfaces. Intl J. Heat Mass Transfer 30, 379–393.Google Scholar
Gaunt, J. A.: 1929 The triplets of helium. Phil. Trans. R. Soc. Lond. A 228, 192–196.Google Scholar
Goldman, A. J., Cox, R. G. & Brenner, H., 1966 The slow motion of two identical arbitrarily oriented spheres through a viscous fluid. Chem. Engng Sci. 21, 1151–1170.Google Scholar
Goldshtik, M. A., Khanin, V. M. & Ligai, V. G., 1986 A liquid drop on an air cushion as an analogue of Leidenfrost boiling. J. Fluid Mech. 166, 1–20.Google Scholar
Gottfried, B. S. & Bell, K. J., 1966 Film boiling of spheroidal droplets. Indust. Engng Chem. Fundam. 5, 561–568.Google Scholar
Gottfried, B. S., Lee, C. J. & Bell, K. J., 1966 The Leidenfrost phenomenon: film boiling of liquid droplets on a flat plate. Intl J. Heat Mass Transfer 9, 1167–1187.Google Scholar
Haber, S., Hetsroni, G. & Solan, A., 1973 On the low Reynolds number motion of two droplets. Intl J. Multiphase Flow 1, 57–71.Google Scholar
Law, C. K.: 1982 Recent advances in droplet vaporization and combustion. Prog. Energy Combust. Sci. 8, 171–201.Google Scholar
Michiyoshi, I. & Making, K., 1977 Heat transfer characteristics of evaporation of a liquid droplet on heated surfaces. Intl J. Heat Mass Transfer 21, 605–613.Google Scholar
Nguyen, T. K. & Avedisian, C. T., 1987 Numerical solution for film evaporation of a spherical liquid droplet on an isothermal and adiabatic surface. Intl J. Heat Mass Transfer 30, 1497–1509.Google Scholar
Oguz, H. N. & Sadhal, S. S., 1987 Growth and collapse of translating compound multiphase drops: analysis of fluid mechanics and heat transfer. J. Fluid Meek. 179, 105–136.Google Scholar
Raznjevic, K.: 1976 Handbook of Thermodynamic Tables and Charts. Hemisphere.
Sadhal, S. S. & Oguz, H. N., 1985 Stokes flow past compound multiphase drops: the case of completely engulfed drops/bubbles. J. Fluid Mech. 160, 511–529.Google Scholar
Sampson, R. A.: 1891 On Stokes's current function. Phil. Trans. R. Soc. Land. A 182, 449–518.Google Scholar
Sen, A. K. & Law, C. K., 1984 On a slowly evaporating droplet near a hot plate. Intl J. Heat Mass Transfer 27, 1418–1421.Google Scholar
Stimson, M. & Jeffery, G. B., 1926 The motion of two spheres in a viscous fluid. Proc. R. Soc. Lond. A 111, 110–116.Google Scholar
Tamura, Z. & Tanasawa, Y., 1959 Evaporation and combustion of a drop contacting with a hot surface. In Seventh Intl Symp. on Combustion, pp. 509–522. Butterworths.
Vargaftik, N. B.: 1975 Handbook of Physical Properties of Liquids and Oases. Hemisphere.