二氧化碳翅片管式蒸发器模拟与分析

运用分布参数法建立采用CO2的翅片管式蒸发器的数学模型，分析制冷剂侧和空气侧温度、压力和换热的变化情况。同时讨论迎面风速和制冷剂质量流量对蒸发器换热和流动性能的影响，结果表明提高迎面风速可以增加换热效果，但增加的趋势趋于平缓。制冷剂侧压降则成近似线性增大；随着管内工质流量的增大，蒸发器总换热量和制冷荆侧压降都成近似线性增大。这些工作有助于进一步了解CO2在翅片管式蒸发器中的换热和流动特性，并为换热器的优化设计和系统的匹配提供理论依据。

The simulation and analysis of fin-tube heat exchanger using CO2 as working fluid

Using the distributed parameter met.hod, the mathematic model of the fin-tube heat exchanger using CO2 as working fluid is derived. The changes of the temperature, pressure and heat transfer on the air and the refrigerant side are analyzed. And the effects of the frontal velocity and the refrigerant mass velocity on the heat transfer and the flow are also discussed. The results show that the higher frontal velocity can improve the heat transfer performance, but increase the pressure drop on the refrigerant side. And the higher refrigerant mass velocity also can enhance the heat transfer, but increase the pressure drop. This work is helpful to understand the heat transfer and the flow characteristics of CO2 in the fin-tube heat exchanger, and offers a theoretical basis for the optimization design of the heat exchanger.