结构形式对椭圆扁管管内传热与流阻性能影响

利用数值模拟方法结合场协同理论,对直椭圆扁管、单向螺旋椭圆扁管和变向螺旋椭圆扁管管内传热与流动情况进行了数值模拟计算和理论分析,比较研究了不同的Re、Pr下,3种椭圆扁管的管内传热与流阻特性。结果表明,单向螺旋椭圆扁管和变向螺旋椭圆扁管与直椭圆扁管相比有很好的强化传热性能,而变向螺旋椭圆扁管要比单向螺旋椭圆扁管的强化传热性能更好。在管内流体具有高Pr及低Re的条件下,2种螺旋椭圆扁管的强化传热效果显著,可作为很好的强化传热元件应用于工程实际中。

Heat transfer and flow friction property in elliptical tube with different structure

Numerical simulation and the theoretical analysis with field synergy principle were carried out for the heat transfer and flow state in the straight elliptical tube,the twisted elliptical tube with one twisting direction and the twisted elliptical tube with changing twisting direction.Heat transfer and flow friction property of the three type elliptical tubes under different Reynolds number and Prandtl number were compared.The results indicate that both the twisted elliptical tube with one twisting direction and changing twisting direction are better than straight elliptical tube from the viewpoint of attaining the effect of heat enhancement,and the twisted elliptical tube with changing twisting direction is better than the twisted elliptical with one twisting direction.Both the two types of twisted elliptical tube have excellent effect of heat enhancement when the fluid in the tubeside has high Prandtl number and low Reynolds number,especially the twisted elliptical tube with changing twisting direction,they can be used as good heat enhance element in the engineering field.