New Three Zone Model for Performance Prediction of Adiabatic Capillary Tubes

A new three zone model of adiabatic capillary tube was presented. The choked flow was taken into account in the model. The subcooled, the two phase and the superheated flow zone were modeled with the mean state parameters. An effective correlation of the mean state parameters to the inlet and outlet state parameters in different flow zone was developed based on the R12 data. Satisfactory effects were kept when the correlation was applied to other refrigerants, such as R134a and R600a. Therefore, it has good flexibility and is suitable for the system simulation of actual refrigeration appliances or engineering calculations.