자연냉매를 사용하는 초저온용 이원 및 이단압축 냉동방식의 운전특성 비교
Comparison of Operation Characteristics of Cascade Refrigeration and 2-Stage Compression System for Ultra-low Temperature using Natural Refrigerants
In this paper, the performance characteristics of a cryogenic refrigeration system used in fields such as HMR(Home Meal Replacement) that require ultra-low temperatures of -50℃ using natural refrigerants according to the recent enforcement of the Atmosphere Environment Conservation Act were investigated. For this purpose, a 2-stage compression refrigeration system using R744(CO2) and a cascade refrigeration system using R747/R404A and R747/R717(NH3) were applied. The COP(coefficients of performance) of each refrigeration system were compared according to changes in evaporation and condensation temperature, subcooled and superheated degree. Although the coefficient of performance of the 2-stage compression refrigeration system using R744 was superior to that of the cascade refrigeration system, 2-stage refrigeration system was considered that various problems should be solved in practical terms. In addition, the COP of R744/R717 for various operating conditions showed similar results to R744/R404A, so the possibility of alternativeness could be confirmed in the cascade refrigeration system.
목차
ABSTRACT 1. 서론 2. 성능분석 2.1 2단압축 냉동방식 2.2 2원 냉동시스템 3. 결과 및 고찰 3.1 증발온도의 영향 3.2 응축온도의 영향 3.3 과열도의 영향 3.4 과냉각도의 영향 4. 결론 후기 References