空气侧换热是制约翅片管换热器发展的一个主要因素,而风机-换热器单元的内部空气流场分布对空气侧的换热影响显著。本文用数值模拟和实验两种手段对一种"U"型翅片管内部空间的空气流场进行了研究。通过商用软件对该空间进行了三维数值模拟,研究结果给出了整场流速的详细分布。用干冰作为材料,对该空间进行了可视化发烟实验。在不同高度的速度分布上,数值模拟与实验结果吻合较好。结果显示正对风机的速度最大,换热最好。本研究为翅片管的优化提供了数据,为本领域的研究者提供了一个新的思路。
The airside heat transfer is a major problem that restrains the development of fin-and-tube heat exchanger,on which the airflow within the space in the unit of fan and heat exchanger has significant influence.In this study,the interior airflow of a U type fin-and-tube heat exchanger is investigated numerically and experimentally.Fluent code is used to simulate the flow in the space and air velocity distribution in the whole field is obtained.Experiment is conducted by using dry ice and a smoke generator is used for fluid flow visualization.The numerical results for the air velocity distribution at different height agree well with the experimental measurements.The velocity in front of the fan is the highest and the heat transfer in this area is stronger.The results provide data for optimization of fin-and-tube heat exchanger and a new ideal for designers in this field.