Document IIF

Coefficient de transfert de chaleur et chute de pression pendant l'évaporation du R1234yf, du R134a et du R22 à l'intérieur de tubes lisses circulaires horizontaux de faible diamètre.

Heat transfer coefficient and pressure drop during evaporation of R1234yf, R134a and R22 in horizontal circular small tubes.

Numéro : pap. n. 2

Auteurs : CHIEN N. B., OH J. T., SAITO K., et al.

Résumé

Experimental data of heat transfer coefficient and pressure drop during evaporation of R1234yf, R134a and R22 in horizontal circular small tubes were compared. The local heat transfer coefficient and pressure drop were obtained for heat fluxes ranging from 10–35 kW/m2, mass fluxes ranging from 100–650 kg/m2.s, saturation temperatures of 5, 10 and 15?, and quality up to 1.0. The test section was made of stainless steel tubes with inner diameters of 1.5 and 3.0 mm, lengths of 1000, 2000 and 3000 mm. Effects of heat flux, inner tube diameter and saturation temperature on heat transfer coefficient are reported in this study. Nucleate boiling heat transfer contribution was predominant, especially at low quality region, and laminar flow appeared in the evaporative small tubes. The experimental results were compared against four existing heat transfer coefficient and new correlation of heat transfer coefficient and pressure drop are developed with good prediction.

Documents disponibles

Format PDF

Pages : 10 p.

Disponible

  • Prix public

    20 €

  • Prix membre*

    Gratuit

* meilleur tarif applicable selon le type d'adhésion (voir le détail des avantages des adhésions individuelles et collectives)

Détails

  • Titre original : Heat transfer coefficient and pressure drop during evaporation of R1234yf, R134a and R22 in horizontal circular small tubes.
  • Identifiant de la fiche : 30006394
  • Langues : Anglais
  • Source : RCR 2012. 3rd IIR Workshop on Refrigerant Charge Reduction in Refrigerating Systems: Valencia, Spain, October 25-26, 2012.
  • Date d'édition : 25/10/2012

Liens


Voir d'autres communications du même compte rendu (21)
Voir le compte rendu de la conférence