Full Description

A model for a steady-state, two-phase flow in capillary tubes, considering the thermodynamic non-equilibrium phenomenon during vaporisation and the relative velocity between the liquid and vapour, has been developed. The five differential equations based on the drift flux model of two-phase flows are solved by using the Runge-Kutta method simultaneously. A comparison in good agreement with experimental data obtained from two-phase flow of Refrigerant-12 flowing through capillary tubes shows that the model is practical and can be used for selection of capillary tubes in refrigerating systems.

KEYWORDS: calculating, thermodynamics, steady state, fluid flow, refrigerants, R12, vaporising, speed, comparing, capillary tubes, selecting, refrigeration.

Citation: ASHRAE Transactions, vol.96, pt. 1, Atlanta, 1990