Modelling of Flashing in Capillary Tubes using Homogeneous Equilibrium Approach

A model for the two phase flow of refrigerant through a capillary tube has been developed. This model assumes mechanical& thermal equilibrium between the phases. The flashing phenomenon occurs when a liquid is out of thermodynamic equilibrium such as sudden changes in the pressure or temperature of a liquid system. The rate of flashing is modeled as proportional to the deviation from the equilibrium vapor pressure. Results of this model compared with experimental data for flow through capillary tube. Also this model is used to calculate the critical flow rate for various inlet conditions. The predictions are compared with experimental data. The concordance between the predictions and the experiments has been discussed in this paper.