Heat transfer analysis of local evaporative turbulent falling liquid films

N. M. Al-Najem, K. Y. Ezuddin, M. A. Darwish

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

A theoretical study has been conducted for evaporative heating of turbulent free-falling liquid films inside long vertical tubes. The methodology of the present work is based on splitting the energy equation into homogeneous and nonhomogeneous problems. Solving these simple problems yields a rapidly converging solution, which is convenient for computational purposes. The eigenvalues associated with the homogeneous problem can be computed efficiently, without missing any one of them, by the sign-count algorithm. A new correlation for the local evaporative heat transfer coefficient along the tube length is developed over wide ranges of Reynolds and Prandtl numbers. Furthermore, the average heat transfer coefficient is correlated as a function of Reynolds and Prandtl numbers as well as the interfacial shear stress. A correlation for the heat transfer coefficient in the fully developed region is also presented in terms of Reynolds and Prandtl numbers. Typical numerical results showed excellent agreement of the present approach with the available data in the literature. Moreover, a parametric study is made to illustrate the general effects of various variables on the velocity and temperature profiles.

Original languageEnglish
Pages (from-to)688-694
Number of pages7
JournalJournal of Heat Transfer
Volume114
Issue number3
Publication statusPublished - 1 Aug 1992
Externally publishedYes

Fingerprint

Prandtl number
Liquid films
heat transfer coefficients
falling
Heat transfer coefficients
Reynolds number
heat transfer
Heat transfer
liquids
tubes
temperature profiles
shear stress
Shear stress
eigenvalues
velocity distribution
methodology
Heating
heating
Temperature
energy

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Physical and Theoretical Chemistry
  • Mechanical Engineering

Cite this

Heat transfer analysis of local evaporative turbulent falling liquid films. / Al-Najem, N. M.; Ezuddin, K. Y.; Darwish, M. A.

In: Journal of Heat Transfer, Vol. 114, No. 3, 01.08.1992, p. 688-694.

Research output: Contribution to journalArticle

Al-Najem, N. M. ; Ezuddin, K. Y. ; Darwish, M. A. / Heat transfer analysis of local evaporative turbulent falling liquid films. In: Journal of Heat Transfer. 1992 ; Vol. 114, No. 3. pp. 688-694.
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