Abstract: A novel algorithm for heat exchanger containing capillaries is presented by developing and applying a model for choked capillary with known inlet refrigerant parameter only into the model for multi-path heat exchanger containing capillaries as well as introducing auxiliary equations into it to redistribute the refrigerant mass flow rate when there are capillaries chocked. The situation of capillaries choked or not during simulation process is concluded into 3 types of no capillary choked, part capillaries choked and all capillaries on all paths choked. The model and algorithm are verified with experimental data. The verification results show that the deviations for predicting re-frigerant flow rate in capillary is less than ±6%, the deviations for predicting heat transfer and pressure drop characteristics of heat exchanger are within ±5% and ±15%, respectively.

Key words: Capillary, Heat exchanger, Simulation