An experimental investigation of flow boiling heat transfer coefficient and pressure drop of R410A in various minichannel multiport tubes

The present work demonstrates the two-phase flow boiling heat transfer coefficient and pressure drop of R410A inside various minichannel multiport tubes. The experimental investigation was performed in four tube types with the hydraulic diameters of 1.16, 1.14, 1.07 and 0.96 mm and the number of parallel channels are 7, 11, 16 and 9, respectively. The data were conducted with the heat fluxes of 3 and 6 kW m−2, the mass flux ranging from 50 to 500 kg m−2 s−1, the saturation temperature of 6 °C and the vapor quality up to 1.0. The heat transfer coefficient of R410A was found to be affected by the heat flux, mass flux, vapor quality and the geometry of channel. The frictional pressure drop gradient was also affected by the mass flux and vapor quality but independent with the variation of heat flux. In addition, the present data were compared with various heat transfer coefficient correlations and pressure drop models in literature. Finally, new correlation of heat transfer coefficient was proposed based on the present experimental data.