Effect of Different Airflow Conditions on Performance of Condenser

Abstract:

A numerical thermal-hydraulic model considering the mal-distribution of refrigerant-side is used to investigate a four passes parallel-flow condenser. The influence of different airflow conditions on the performance and refrigerant distribution characteristic of this condenser is given. The related airflow conditions are inlet blockage, front radiator and different number of cooling fans. The results are as follows. At 50% blocking rate, the middle blocking mode makes the most deterioration of the performance of the condenser, heat transfer rate decreases 47.9% and refrigerant pressure drop increases 335.5%. The different blocking modes have different effects on the flow distribution of the refrigerant side, and the unevenness of the refrigerant distribution caused by grille block is the largest. The partial air velocity reduction and temperature increase caused by a front radiator results in 24.1% decrease in heat transfer and 80% increase in refrigerant pressure drop of the condenser. The front radiator only influences the refrigerant flow distribution of the second pass. When total air flow is constant, different number of cooling fans have little effect on heat transfer and pressure drop, but the unevenness of the refrigerant distribution is obviously increased.

Key words:parallel flow condenser; airflow condition; heat transfer performance; refrigerant pressure drop; refrigerant mal-distribution