Document IIF

Configuration d'écoulement, transfert de chaleur et chute de pression lors de l'évaporation et la condensation du R134A à l'intérieur des tubes à micro-ailettes

Flow patterns, heat transfer and pressure drop for evaporation and condensation of R134A in microfin tubes.

Auteurs : COLOMBO L. P. M., LUCCHINI A., MUZZIO A.

Type d'article : Article, Article de la RIF

Résumé

Experiments on flow boiling and convective condensation for oil-free R134a were performed with three 9.52 mm outer diameter tubes (two microfined and one smooth) horizontally operated and heated or cooled by a water stream. Microfin tubes have sharp fins (apex angle 40°) alternating with two different heights whereas the fin number is different (54 and 82). For evaporation (5°C nominal temperature) test conditions were set as: mass flux 100÷340 kg (m2/s), inlet quality 0.25÷0.70, quality change 0.10÷0.70; for condensation (35°C nominal temperature): mass flux 100÷440 kg (m2/s), inlet quality 0.75÷0.10, quality change 0.10÷0.70. Average heat transfer coefficients and pressure drop were measured. Furthermore, a visual inspection was performed to characterize how fins affect the flow pattern transitions. Finally, experimental data and prediction of well-known correlations proposed for these tubes were compared.

Documents disponibles

Format PDF

Pages : 2150-2165

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 : Flow patterns, heat transfer and pressure drop for evaporation and condensation of R134A in microfin tubes.
  • Identifiant de la fiche : 30005966
  • Langues : Anglais
  • Source : International Journal of Refrigeration - Revue Internationale du Froid - vol. 35 - n. 8
  • Date d'édition : 12/2012

Liens


Voir d'autres articles du même numéro (26)
Voir la source