Capillary tubes are widely used as a refrigerant flow control device in small refrigeration systems. Since the flow behavior inside the capillary tube is complex, many physical models are necessary to predict the characteristics of the refrigerant flow in a capillary tube. In the present paper, refrigerant flow characteristics inside the capillary tube have been studied to find out recommended empirical correlations of influential parameters. A numerical capillary model is developed to predict the refrigerant characteristics. Various empirical correlations regarding single-phase friction factor, two-phase viscosity, two-phase frictional multiplier and metastable flow are examined using this numerical capillary model. Calculated results are compared with experimental data to examine the accuracy in terms of required capillary tube length and mass flow rate. Based on the comparison, recommended correlations are selected to be used for capillary flow analysis.