R1224yd(Z) Flow Boiling inside a Mini Microfin Tube

摘要

This paper presents the R1224yd(Z) flow boiling heat transfer and pressure drop measurementsinside a mini microfin tube with internal diameter at the fin tip of 4.2 mm. The microfin tube wasbrazed inside a copper plate and electrically heated from the bottom. Sixteen T-type thermocouplesare located in the copper plate to monitor the wall temperature. The experimental measurementswere carried out at constant mean saturation temperature of 30°C, by varying the refrigerant massvelocity between 100 kg m~(-2) s~(-1) and 200 kg m~(-2) s~(-1), the vapor quality from 0.3 to 0.95, at three differentheat fluxes: 15, 30, 60 kW m~(-2). The experimental results are presented in terms of two-phase heattransfer coefficient, onset dryout vapor quality, and frictional pressure drop. This new HFO fluidshows promising heat transfer capabilities, which makes it a possible viable substitute of the high-GWP, low-pressure refrigerants.