Condensation of HFC-134a and HFC-404a in a Smooth and Micro-Fin Tube

The purpose of this work was to study the condensation heat transfer and pressure drop characteristics ofHFC-134a in a micro-fined tube with an 18 degree helix angle and to compare them to those in a smooth tube for various operating conditions.The experimental test facility is designed, developed and is used to determine the condensation HTC and pressure drop in smooth and micro-fin tubes for various HFC refrigerants namely HFC-134a, R-404A, R-407C, R-507A. The experimentation covers wide range of operating parameters such as mass flux and condensing temperatures. The instrumentations used for measurements are calibrated from recognized calibration centres. The hermetically sealed compressor is used for circulating refrigerant; effect of oil present in the refrigerant during condensation is also taken into account. The condensation of HFC-134a and R-404A in smooth and micro-fin tubes are measured and obtained the values of condensation HTCs and pressure drops for different mass flux and condensing temperatures