三维针翅片管在螺旋板换热器应用传热强化研究

将光滑管外表面进行滚压—犁切复合加工,形成了三维A型针翅片管,应用于连续形的螺旋导流板换热器中,流体在连续形螺旋导流板换热器的壳程中类似于塞状流流动,几乎没有返混和流动死区。在相同压降下,其传热系数比普通的弓形折流板换热器高得多。文章以润滑油作为实验介质,研究了润滑油在螺旋导流板三维A型针翅片管换热器的壳程传热和压降性能,并与光滑管螺旋导流板换热器进行了性能对比。实验结果表明,在相同Reynolds数下,螺旋导流板三维A型针翅片管换热器的Nusselt数和压降△p分别是光滑管螺旋导流板换热器的2.4～2.8倍和1.2～1.4倍。与光滑管螺旋导流板换热器相比,螺旋导流板三维A型针翅片管换热器的传热性能的提高远高于压降的提高,证明在螺旋流条件下,三维A型针翅片管具有很好的传热强化性能。

The Heat Transfer Enhancement Study of 3 d Type Needle Finned Tube Used in Helical Guide Plate Heat Exchanger

On the smooth tube surface rolling processing plough cut-compound,formed the 3 d type a needle finned tube,and the application of the continuous form helical guide plate heat exchanger.The flow pattern on the shell side of a helically guide plate heat exchanger is near plug flow conditions,which almost eliminates backmixing and dead space on the shell side.The heat transfer coefficient of the helically guide plate heat exchanger is much higher than that of conventional segmental baffle heat exchanger at the same pressure drop,In this paper,experiments were conducted for cooling water flowing in the tube side on the helically guide plate heat exchanger with lubricating oil as the working medium flowing on the shell side.Study helically guide plate 3 d type a needle finned tube heat exchanger shell heat transfer process and pressure drop in performance,and with that of smooth tube helically guide plate heat exchanger was the performance comparison.The results showed that the Nusselt numbers and pressure drops on the shell side of the helically guide plate guide plate heat exchanger with petal-shaped finned tube were 2.4~2.8 and l.2~1.4 times larger than those of the helically guide plate heat exchanger with smooth tube at constant Reynolds number,respectively.The 3d type A needle finned tube could significantly improve the shell side heat transfer performance for the helically guide plate heat exchanger.