| Titre : | Periodical reverse flow and boiling fluctuations in a microchannel evaporator of an air-conditioning system (2013) |
| Titre original : | Ecoulement inverse périodique et fluctuations de l'ébullition dans l'évaporateur à microcanaux d'un système de conditionnement d'air |
| Auteurs : | Hanfei Tuo, Auteur ; Pega Hrnjak, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | International journal of refrigeration (Vol. 36 N° 4, Juin 2013) |
| Article en page(s) : | pp. 1263–1275 |
| Note générale : | Refrigeration |
| Langues : | Anglais |
| Tags : | Periodic reverse flow ; Flow visualization ; Boiling fluctuation ; Microchannel evaporator |
| Résumé : | This paper presents the phenomenon of periodic reverse flow and associated boiling fluctuation found in experiments with a parallel microchannel evaporator used in an R134a air conditioning system. A simultaneous flow visualizations and measurements confirmed the periodic flow reversal. It caused synchronized oscillations of the evaporator inlet pressure and the pressure drop. The magnitude and frequency of oscillations increased with heat flux. Three potential impacts of flow reversal on evaporator performance are identified: 1) moderate liquid maldistribution; 2) reduced heat transfer coefficient; 3) increased refrigerant side pressure drop. Finally, to mitigate impacts of periodic reverse flow, a solution is proposed: to vent and bypass backflow vapor accumulated in the inlet header. |
| En ligne : | http://www.sciencedirect.com/science/article/pii/S0140700713000236 |
