In this paper, cycle performance analysis of cascade refrigeration system using natural refrigerants R744 for low temperature cycle, and R290, R600, R600a, R717 for high temperature cycle are presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooled and superheated degree, and condensing and evaporating temperature, temperature difference of cascade heat exchanger in cascade refrigeration system. The COP of cascade refrigeration system increases with the increasing subcooled degree, but there is no significant changes with the increasing superheated degree. The COP of cascade refrigeration system depends on evaporating and condensing temperatures of cascade heat exchanger. The COP of cascade refrigeration system using natural refrigerants is similar to the COP using freon refrigerant (R23 / R22). Points to be considered are th security, the attached facilities for natural refrigerants than COP.

Abstract
 1. 서론
 2. 성능 분석
 3. 본론
  3.1 절 과냉각도의 영향
  3.2절 과열도의 영향
  3.3절 증발온도의 영향
  3.4절 캐스케이드 열교환기의 영향
 4. 결론
 참고문헌

• 노건상(동명대학교 공과대학 냉동공조공학과) | Roh, Geonsang