A study on the solar assisted heating system with refrigerant as working fluid

냉매를 작동유체로 사용하는 태양열 난방시스템에 관한 연구

  • Kim, Ji-Young (Dept. of Mechanical Engineering, Graduate School, Cheju National University) ;
  • Ko, Gawng-Soo (Dept. of Mechanical Engineering, Graduate School, Cheju National University) ;
  • Park, Youn-Cheol (Faculty of Mechanical, Energy and System Engineering, Cheju National University)
  • 김지영 (제주대학교 대학원 기계공학과) ;
  • 고광수 (제주대학교 대학원 기계공학과) ;
  • 박윤철 (제주대학교 기계에너지시스템공학부)
  • Published : 2005.12.30

Abstract

An experimental study was conducted to analyze performance of a heating system with variation of control logic of the system. The system uses a solar as heat source and composed with heat pump that uses R-22 as working fluid. The difference between the developed system and the commercially available heating system is working fluid. The solar assisted heating system which was widely distributed in the market uses water as a working fluid. It could be freezing in case of the temperature drops down under freezing point. The anti-freezing fluids such as methyl-alcohol or ethylene-glycol are mixed with the water to protect the freezing phenomena. However, the system developed in this study uses a refrigerant as a working fluid. It makes the system to run under zero degree temperature conditions. Another difference of the developed system compare with commercial available one is auxiliary heating method. The developed system has removed an auxiliary electric heater that has been used in conventional solar assisted heating system. Instead of the auxiliary electric heater, an air source heat exchanger which generally used as an evaporator of a heat pump was adapted as a backup heating device of the developed system. As results, an efficiency of the developed system is higher than a solar assisted heat pump with auxiliary electric heater. The merit of the developed system is on the performance increment when the system operates at a lower solar energy climate conditions. In case of the developed system operates at a normal condition, COP of the solar collector driven heat pump is higher than the air source heat exchanger driven heat pump's.

Keywords

References

  1. Journal of the Korea Solar Energy Society v.25 no.2 Performance of Solar Thermal System by On-Off Differential Temperature of Differential Temperature Controller Shin, U.-Cheul;Baek, Nam-Choon
  2. SAREK 2001 Summer Conference Performance of Dual Source Heat Pump System with Solar with Solar-Assisted Evaporator Baek, Nam-Choon;Lee, Jin-Kook;Song, Byoung-Ha