Non-adiabatic capillary tube flow with isobutane

This work reports the results of an experimental study on concentric capillary tube–suction line heat exchangers commonly used as expansion devices in household refrigerators and freezers. Heat exchanger performance (mass flow rate and suction line outlet temperature) with the hydrocarbon HC-600a was experimentally evaluated for a range of heat exchanger geometries and operating conditions. The tests were planned and performed following a statistically based methodology. Based on the resulting database empirical correlations were developed to predict the refrigerant mass flow rate and the suction line outlet temperature.