NH₃와 R22의 냉동장치에 대한 성능에 관한 실험적연구

Abstract

The ammonia refrigerant has been widely used because of its outstanding properties such as good heat conductivity, and high critical temperature and pressure, but it has disadvantages such as toxicity, inflammability and explosiveness. Thus, this study apply the NH₃ and R22 to study the performance characteristic from the superheat control and compare the energy efficiency of two refrigerants from the high performance. The condensing pressure of refrigeration system is increased from 15bar to 16bar and degree of superheat is increased from 0 to 10℃ at each condensing pressure. As the result of experiment, when comparing the each COP, we knew the NH₃ is suitable as the alternative refrigerant of the R22. This study conducted the comparative analysis of performance of refrigerating systems using NH₃ and R22 with respect to the change in condensing pressure and superheat and the results are presented as follows. 1. The refrigerant mass flow was more steady NH₃ than R22. 2. For both NH₃ and R22, at the same condensing pressure, as the superheat increases, the energy was lost plentifully. Because, the refrigerant mass flow was decreased and compression ratio was increased. ₃. When the degree of superheat is 2℃, the COP was higher NH₃ than R22. When the degree of superheat is 1℃ according to condensing pressures, the COP was the highest for NH₃. When the superheat was 0, the COP was the highest for R22. 4. We knew the NH₃ is suitable as the R22 alternative refrigerants.