Experimental Study of An Indirect-Refrigeration System with Carbon Dioxide

Title & Authors
Experimental Study of An Indirect-Refrigeration System with Carbon Dioxide
Kim, Yoonsup; Baik, Wonkeun; Yun, Rin;

Abstract
Experimental studies for an indirect R404A-$\small{CO_2}$ refrigeration system and a direct R404A refrigeration system were conducted. The configurations of the indirect R404A-$\small{CO_2}$ refrigeration system are a R404A refrigeration system as a top cycle and a circulating $\small{CO_2}$ system as a bottom cycle. The direct R404A system was modified from indirect R404A-$\small{CO_2}$ refrigeration system by removing circuit for $\small{CO_2}$ circulation. Various tests for both systems were conducted by changing load side brine temperature from 0 to 5 and $\small{10^{\circ}C}$ with cooling brine temperatures for R404A system at 15, 20, or $\small{25^{\circ}C}$. The indirect R404A-$\small{CO_2}$ refrigeration system showed the highest COP when load side brine temperature was at $\small{10^{\circ}C}$ in the evaporator and at cooling brine temperature of $\small{15^{\circ}C}$. The COP of 3.04 under that condition was the highest. This indirect R404A-$\small{CO_2}$ refrigeration system showed 9.02% higher COP than the direct R404A system that had increased pipeline length of 15 m, which simulated actual installation in a supermarket.
Keywords
Language
Korean
Cited by
References
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