Intégration d'un échangeur de chaleur à microcanaux dans un système à pompe à chaleur réversible.

Integration of a microchannel heat exchanger in a reversible heat pump system.

Résumé

This paper presents results from the integration of a microchannel heat exchanger (MCHEX) into a conventional R-410A reversible air-to-water heat pump system. This implementation is made assuming equal face areas for the heat exchangers analyzed. The overall goal of the investigation is to achieve an easy integration of the MCHEX into the baseline unit and an efficiency increase in both heating and cooling modes. The impact of utilizing a MCHEX on refrigerant charge and refrigerant distribution, along with frosting concerns are also evaluated. The baseline unit was tested to establish operating conditions for properly designing the MCHEX into the heat pump system. The new system, equipped with the MCHEX, shows very encouraging results in terms of refrigerant charge reduction (nearly 50% versus baseline unit) and efficiency gain (about 12%) for cooling mode. Tests performed in heating mode demonstrate similar frosting characteristics to the baseline unit and successful draining of the condensed humidity. Distribution patterns of the liquid refrigerant in two phase-flow indicate inadequate circuiting, which leads to approximately equal performance with the baseline unit instead of an anticipated increase. Analysis of the MCHEX circuiting with a thermal imaging camera has identified areas for further design improvements In collaboration with the heat exchanger manufacturer, several coil design were constructed. Subsequent testing under heating mode showed that fluid distribution was significantly improved in these coils, and yielded a slightly higher heating mode performance.

Détails

  • Titre original : Integration of a microchannel heat exchanger in a reversible heat pump system.
  • Identifiant de la fiche : 2008-1248
  • Langues : Anglais
  • Date d'édition : 20/11/2006
  • Source : Source : Climamed 2006, Lyon
    PIII-2.5; 287-295; fig.; phot.; tabl.; 5 ref.