23 April 2019
A new type of evaporator, falling film, was tested, allowing low refrigerant charges. Under certain conditions, the heat transfer performance was better than a for traditional flooded evaporator. The effects of different refrigerant charges, tube pass arrangements and refrigerant types on the falling film evaporator were analyzed. The results showed that with the increase of refrigerant charge, the heat transfer performance was improved gradually, but the trend was gradually slower. The bottom-to-top tube pass arrangement provided a better performance than the top-to-bottom tube pass arrangement. The falling film evaporation centrifugal chiller with R1233zd (E) provided a higher COP when the refrigerant charge reached a certain amount.