The results about the performance of a new DAR's thermodynamic model are compared with the predictions of Zohar et al. (2009). The main difference is due to an accurate modeling of the refrigerant composition, assumed there as pure ammonia. A sensitivity analysis shows that, as the generator temperature increases, the rich solution mass flowrate reduces more than that of the refrigerant one, and COP decreases. This happens as the absorption temperature increases as well, due to the lower absorption of ammonia in the weak solution. COP was found to increase when the ammonia concentration decreases. In addition, for lower heat fluxes supplied to the generator, the heat dissipation toward ambient dominates and COP becomes small; when the heat flux overtakes a threshold, the evaporator reaches its maximum heat transfer, that remains constant for any further increase of heat supplied. COP presents its highest values over a limited range of the generator's operating conditions.

An advanced analytical model of the Diffusion Absorption Refrigerator cycle

2012

Abstract

The results about the performance of a new DAR's thermodynamic model are compared with the predictions of Zohar et al. (2009). The main difference is due to an accurate modeling of the refrigerant composition, assumed there as pure ammonia. A sensitivity analysis shows that, as the generator temperature increases, the rich solution mass flowrate reduces more than that of the refrigerant one, and COP decreases. This happens as the absorption temperature increases as well, due to the lower absorption of ammonia in the weak solution. COP was found to increase when the ammonia concentration decreases. In addition, for lower heat fluxes supplied to the generator, the heat dissipation toward ambient dominates and COP becomes small; when the heat flux overtakes a threshold, the evaporator reaches its maximum heat transfer, that remains constant for any further increase of heat supplied. COP presents its highest values over a limited range of the generator's operating conditions.
Absorption; Diffusion absorption refrigerator; Analytical Model; Refrigeration cycle; Diffusion system
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.12572/737
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
social impact