냉동오일을 포함한 여러냉매에 대한 증발기 성능해석

The computer modeling for prediction of the performance of fin-tube heat exchanger using various refrigerants(CFC-12, HCFC-12, HFC-134a)with and without oil is performed. The heat exchanger modeling is based on a tube-by-tube method, which is capable of analysis for the complex coil array. Performance of each tube is analyzed separately by considering the cross-flow heat transfer with external airstream and the appropriate heat and mass transfer relationships. Performance comparisons according to the different refrigerants with oils(150SUS and 300SUS)and wiyhout oil are provided using this developed model. As the result of this study, total pressure drop of oil-refrigerant mixture increases as oil concentration increases from 0 % to 5 %, whether oil is 150-SUS or 300-SUS. Heat transfer rate of oil-refrigerant slightly increased for 5 % oil-refrigerant mixture at 150-SUS and conversely at 300-SUS