Characteristics on condensation heat transfer and pressure drop for a low GWP refrigerant in brazed plate heat exchanger

Abstract

Refrigerants have been continuously developed to improve their thermal performances and to deal with relevant environmental issues. Recently, regulations on refrigerants are being intensified due to the global warming. To meet the enhanced environmental standards, low global warming potential (GWP) refrigerants have been developed. In this study, experimental studies are conducted to investigate the characteristics of condensation heat transfer and frictional pressure drop for R-1233zd(E). The experiments are carried out under partial condensation conditions in a plate heat exchanger to measure temperature, pressure and mass flow rate. Heat transfer coefficients and frictional pressure drops with respect to mean vapor qualities are yielded. During the partial condensation process, the heat transfer coefficients increases as the mass and heat fluxes increase. However, no significant change in frictional pressure drop is observed when the heat flux changes. It is concluded that other correlations for Nusselt number and pressure drop from the literature cannot be applied for the low GWP refrigerant, R-1233zd(E), and the present experimental correlations agree well with the experimental results with the error bands of ±20%.