International Scientific Journal

Thermal Science - Online First

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Effect of the non condensable gas type during condensation of water vapor

In this paper, a numerical study is performed to investigate the influence of the non-condensable gas type in a vapor mixture of water-gas (water vapor-Krypton, water vapor-Argon, water vapor-Air and water vapor-Neon) during the condensation along a vertical pipe with a wall cooled by air flow. The applied numerical method solves the coupled parabolic governing equations in both gas and liquid phases with the appropriate boundary and interfacial conditions. The equations systems, obtained by using an implicit finite difference method are solved by Thomas algorithm. The numerical results obtained show that the heat and mass transfer is influenced by increasing the molar mass of non-condensable gases. The comparisons of air mass fraction, bulk temperature, local condensate heat transfer coefficient and average Nusselt number of sensible heat with the literature results and the available experimental data are in good agreement.
PAPER REVISED: 2016-11-02
PAPER ACCEPTED: 2016-11-07
  1. Nusselt W.,The condensation of steam on cooled surfaces (Traduit par D. Fullarton), Zeitschrift des Vereines Deutscher Ingenieure, (1916).Vol. 60, n. 27, pp. 541-575.
  2. Rohsenow W.M., Heat transfer and temperature distribution in laminar film condensation.Trans. ASME. (1956), 78:1956-1648.
  3. Siddique M., Golay M.W., Kazimi M.S, Local heat transfer coefficients for forced-convection condensation of steam in a vertical tube in the presence of noncondensable gas. Nuclear Technology (1993), 102, pp. 386 - 402.
  4. Siddique M., Golay M.W., Kazimi M.S., Theoretical modelling of forced-convection condensation of steam in a vertical tube in the presence of a noncondensable gas. Nuclear Technology (1994), 106, 202-215.
  5. Merouani L., Zeghmati B., Belhamri A., Numerical modelling of convective vapour condensation with non-condensable gases between two coaxial vertical cylinders. The Canadian Journal of Chemical Engineering. september (2013), Vol 91.pp.1597-1607.
  6. Maheshwari N.K., Saha D., Sinha R.K., Aritomi M., Investigation on condensation in presence of a noncondensable gas for a wide range of Reynolds number. Nuclear Engineering and Design (2004), 227, 219-238.
  7. Oh S., Revankar S.T., Effect of noncondensable gas in a vertical tube condenser. Nuclear Engineering and Design, (2005), 235, No 16, 1699-1712.
  8. Saffari H. and Dalir N., effect of virtual mass force on prediction of pressure changes in condensing tubes. Thermal Science, (2012), vol. 16, no. 2, pp. 613-622.
  9. El Hammami Y., Feddaoui M., Mediouni T., Mir A., Numerical study of condensing a small concentration of vapour inside a vertical tube. Heat and Mass Transfer (2012), 48: 1675-1685,
  10. Hassaninejadfarahani F., Guyot M.K., Ormiston S.J., Numerical analysis of mixed convection laminar film condensation from high air mass fraction steam-air mixtures in vertical tubes. International Journal of Heat and Mass Transfer (2014), 78 170-180.
  11. Zine-Dine K., El Hammami Y., Mir R., Mediouni T., Armou S., Numerical Study of Laminar Film Condensation inside a Vertical Tube Subjected to Wall Non Uniform Heat Flux. International Journal of Enhanced Research in Science, Technology & Engineering. (2016), Vol. 5 Issue 2, February.
  12. Lebedev P. D., Baklastov A. M., Sergazin F. Z., Aerodynamics heat and mass transfer in vapour condensation from humid air on a flat plate in a longitudinal flow in asymmetrically cooled slot. Int J Heat Mass Transf, (1969).12:833-841
  13. Patankar S. V., Numerical Heat Transfer and Fluid Flow, Hemisphere/Mc Graw-Hill, (1980), New York.Chap.6.