摘要
为了获得换热器肋侧换热系数定义用比较普适的特征温度,采用分区求解、边界耦合方法与非耦合方法对扁管翅片式换热器三维模型的流动与传热性能进行了数值模拟,得到了换热器在不同肋片材料和不同雷诺数下用不同特征温度定义肋侧换热系数的区别,并将数值结果与实验结果进行比较.结果表明:当特征温度不同时,肋侧换热系数数值结果不同;当Re小于1 000和用非耦合计算时,与实验值吻合最好的是以流动进出口平均温度为特征温度的数值结果;而Re大于1 000后,耦合计算时以流动进出口平均温度为特征温度数值结果与实验值更靠近.
To obtain an appropriate characteristic temperature in the definition of the fin side surface heat transfer coefficient, flow and heat transfer characteristics of a flat tube bank fin heat exchanger are simulated by coupled and non-coupled numerical methods. Heat transfer coefficient of the fin side surface under different materials and Reynolds numbers is obtained. The numerical results obtained by two algorithms are compared with experimental data. It shows that the fin side surface heat transfer coefficient is different if the characteristic temperature is selected differently. The numerical result using the average temperature of the fin side fluid as the characteristic temperature agrees well with the experimental results when Re is less than 1 000 and the non-coupled method is adopted. The results are the same when Re is larger than 1 000 and the coupled method is used.
出处
《兰州交通大学学报》
CAS
2012年第3期84-87,共4页
Journal of Lanzhou Jiaotong University
关键词
扁管
翅片换热器
特征温度
肋侧换热系数
数值分析
flat tube
bank fin heat exchanger
characteristic temperature
heat transfer coefficient
numerical analysis
