Partager

Document IIF

Étude expérimentale de la rétention d'huile dans les évaporateurs à microcanaux des systèmes de pompes à chaleur aérothermiques.

Experimental study of oil retention in microchannel type evaporators of air-source heat pump systems.

Auteurs : CREMASCHI L., YATIM A. S., MULUGURTHI S. K.

Type d'article : Article, Article de la RIF

Résumé

In air-source heat pump systems, lubricant is often used with refrigerant compressors and, a small portion of oil, which is inevitably discharged by the compressor, circulates with the refrigerant across the systems components. Oil tends to accumulate in heat exchangers, increasing the pressure losses and reducing the heat transfer capacity. In addition to energy efficiency degradation, safe and reliable operations of the compressors can be compromised by unknown amounts of oil retained in the heat exchangers.

In the present paper, the lubricant retention in two microchannel type evaporators for residential air heat pump systems was measured and the oil effects on evaporator heat transfer capacity and refrigerant-side pressure drop were investigated. Refrigerant R410A was investigated with polyolester lubricant that had a viscosity grade of 32. Saturation temperature was controlled from 0.5°C and up to 9°C and the impact of the degree of refrigerant vapor superheat at the evaporator outlet on the oil retention in the heat exchanger was significant. At high oil concentration, 13% of the internal volume of the evaporators was occupied by lubricant that was either retained or in circulation with the refrigerant inside the evaporators. When oil concentration was below 1 wt.%, which is typical in today's systems, the retained oil was about 10% of the internal volume, pressure losses increased up to 25% and the heat transfer capacity was reduced by 4%.

Documents disponibles

Format PDF

Pages : 158-166

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 : Experimental study of oil retention in microchannel type evaporators of air-source heat pump systems.
  • Identifiant de la fiche : 30023998
  • Langues : Anglais
  • Source : International Journal of Refrigeration - Revue Internationale du Froid - vol. 91
  • Date d'édition : 07/2018
  • DOI : http://dx.doi.org/10.1016/j.ijrefrig.2018.04.022

Liens


Voir d'autres articles du même numéro (25)
Voir la source

Indexation