Saturated vapor condensation of hydrocarbons inside a 4 mm ID smooth tube

This paper presents the comparative analysis of three hydrocarbon refrigerants: R600a (isobutane), R290 (propane) and R1270 (propylene) in saturated vapor condensation inside a 4 mm ID horizontal smooth tube. New experimental tests were carried out with R600a at 40 °C of saturation temperature, with refrigerant mass flux in the range 75–300 kg m −2 s −1, whereas the same authors (Longo et al. 2017) previously presented measurements for propane and propylene, at the same operating conditions. On the basis of the heat transfer data, the transition from gravity dominated and forced convection condensation was investigated. The experimental heat transfer coefficients and frictional pressure drop in the forced convection condensation regime were then compared against some correlations available in literature.