Partager

CO2 dans un tube lisse horizontal : transfert de chaleur lors de l'ébullition et phénomène d'assèchement.

Boiling heat transfer and dryout phenomenon of CO2 in a horizontal smooth tube.

Auteurs : YUN R., KIM Y., KIM M. S., et al.

Type d'article : Article

Résumé

The evaporation heat transfer characteristics of carbon dioxide (CO2) in a horizontal smooth tube were experimentally investigated. The experiments were conducted at saturation temperatures of 5 and 10 °C, mass fluxes of 170 to 320 kg/m2 s and heat fluxes of 10 to 20 kW/m2. Partial dryout of CO2 occurs at a lower quality as compared to the conventional refrigerants due to higher bubble growth within the liquid film and higher liquid droplet entrainment, resulting in a rapid decrease of heat transfer coefficients. The effects of mass flux, heat flux, and evaporating temperature are explained by introducing unique properties of CO2, flow patterns, and dryout phenomenon. The heat transfer coefficient of CO2 is on average 47% higher than that of R134a under the same operating conditions. The Gungor and Winterton correlation poorly predicts the boiling heat transfer coefficient of CO2 at low mass flux, but yields a good estimation at high mass flux.

Détails

  • Titre original : Boiling heat transfer and dryout phenomenon of CO2 in a horizontal smooth tube.
  • Identifiant de la fiche : 2004-1082
  • Langues : Anglais
  • Source : International Journal of Heat and Mass Transfer - vol. 46 - n. 13
  • Date d'édition : 06/2003

Liens


Voir d'autres articles du même numéro (9)
Voir la source

Indexation