축열을 이용한 저온저장고 증발기의 제상에 관한 연구

다국어 초록 (Multilingual Abstract)

In refrigeration systems, the performance of refrigerator decreases due to frost on evaporator surface. In order to increase the performance of the refrigeration system, the frost must be necessarily removed.
Generally the refrigerator is adopted the defrosting method by using an electric heater(EHD), which consumes 15 % of the power for the system operation. And it is necessary to develope more efficient defrosting method than EHD. In this study, the frost phenomenon is observed to a fin-tube heat exchanger(FTHX)
in an environment cold storage experimentally. And a defrosting method by using thermal energy storage(TSD) is experimented to the fin-tube heat exchanger and compared with EHD. At results, as the relative humidity and temperature in the environment cold storage increases, the amount of frost increases. When the same number of columns and the flow path in FTHX is used on the EHD and TSD, the efficiency of EHD is from 55.3 to 73.5 %. The efficiency of TSD is from 232.2 to 420.7 %.
In conclusion, TSD(50℃) is three to six times higher efficiency than of the defrost electric heater(EHD) and the thermal storage temperature is lowered to 10℃ than defrost electric heater one. As the thermal storage temperature decreases, the efficiency of defrost power decreases but heat efficiency increases. Therefore, the lower the temperature of the thermal storage, the storage in the load is reduced due to defrost.
EHD method of defrosting a refrigeration system has confirmed that the method can be a substitute for TSD. By selecting an appropriate thermal storage materials to accept the TSD method affected by the outside air temperature to defrost should be applied to the system.

목차 (Table of Contents)

• 제 1 장 서 론 1
• 1.1 연구 배경 1
• 1.2 연구 동향 3
• 1.3 선행 연구 5
• 1.4 연구 내용 7
• 제 2 장 기초 이론 8
• 2.1 착상(Frost) 8
• 2.2 제상(Defrost) 8
• 제 3 장 실험장치 및 방법 12
• 3.1 실험장치 12
• 3.2 실험방법 및 조건 18
• 제 4 장 실험 결과 및 고찰 24
• 4.1 착상실험 결과 24
• 4.2 전기히터 제상(EHD) 결과 28
• 4.3 축열제상(TSD) 결과 35
• 4.4 전기히터방식 및 축열방식의 제상효율 비교 47
• 제 5 장 결 론 53
• 참 고 문 헌 55