microchannel, charge reduction, COP improvement, modeling
This paper presents an experimentally validated simulation model developed to obtain accurate prediction of evaporator microchannel heat exchanger performance and charge. Effects of using various correlations are presented and discussed with focus on serpentine microchannel evaporators. Experiments with propane are used to validate the model. The experimentally validated model is used to compare the charge reduction potential of various refrigerants. The procedure for charge reduction analysis described in the paper is the reduction of the internal (refrigerant) volume of the evaporator until an evaporator pressure drop is obtained that results in a 2% decrease in COP from the refrigeration cycle with no pressure drop.