| Titre : | Flow pattern map, heat transfer and pressure drops during evaporation of R-1234ze(E) and R134a in a horizontal, circular smooth tube : experiments and assessment of predictive methods (2013) |
| Titre original : | Configuration de l'écoulement, transfert de chaleur et chutes de pression pendant l'évaporation de R-1234ze(E) et de R134a à l'intérieur d'un tube lisse circulaire : expériences et évaluation des méthodes prévisionnelles |
| Auteurs : | S. Grauso, Auteur ; R. Mastrullo, Auteur ; A.W. Mauro, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | International journal of refrigeration (Vol. 36 N° 2 (N° spécial), Mars 2013) |
| Article en page(s) : | pp. 478–491 |
| Note générale : | Refrigeration |
| Langues : | Anglais |
| Tags : | R-1234ze(E) ; R134a ; Flow boiling ; Heat transfer coefficients ; Adiabatic pressure drops ; regimes ; Predictive methods |
| Résumé : |
This paper presents experimental results for local heat transfer coefficients, adiabatic frictional pressure gradients and two-phase flow regimes with the low-GWP refrigerant R-1234ze(E), compared to Hydro-Fluoro-Carbon refrigerant R-134a in the same conditions.
In particular the results refer to an experimental investigation carried out in a circular smooth tube of 6.00 mm of inner diameter, for saturation temperatures between −2.9 °C and 12.1 °C, mass fluxes between 146 and 520 kg m−2 s−1 and heat fluxes between 5.0 and 20.4 kW m−2. These experimental results are compared to those for R-134a at the same operating conditions. Moreover, an assessment of predictive methods is provided for local heat transfer coefficients and frictional pressure gradients; also a direct comparison of flow regimes visualizations for R-1234ze(E) with a flow pattern map available in literature is presented. |
| En ligne : | http://www.sciencedirect.com/science/article/pii/S0140700712001867 |
