Engineering and Technology Journal

In this paper adiabatic flow in capillary tube is analyzed and modeled for R-22 and
alternative R-407C. The equations of continuity, energy and pressure drop through a
capillary tube are presented. A mathematical model of sub–cooled flow region and
two–phase flow region is developed. The results of the calculation compared with
experimental data presented in the technical literature will be shown in the present
article in order to validate the model developed. This numerical model is capable of
providing an effective means to analyze capillary tube performance to optimize and
control an R – 22 and R – 407C in an air – conditioning systems.