以60%甘油水溶液为管程介质,对内置螺旋开槽两叶片转子换热管过渡区内的强化传热综合性能进行了实验研究。在雷诺数范围为2800~6200之间对光管性能进行了实验验证,以保证实验结果的可靠性。同时,对比分析了转子外径对其强化传热性能的影响,研究结果表明:内置转子强化管的努塞尔数Nu较光管约提高了60%~200%,阻力系数较光管约增大了16%~32%,综合评价因子PEC值介于1.56~2.79之间。此外,内置转子强化管的努塞尔数、阻力系数以及PEC值均随着转子外径的增大而增加,这是由于较大的转子外径使得转子具有更强的扰流与减薄边界层的作用。
This research focused on the investigation of comprehensive heat transfer enhancement performances of the tube inserted with helical blade rotors with grooves. A 60% Glycerin solution was used as tube-side working fluid in transition region. In order to ensure the reliability of the experimental results, plain tube validation experiments were carried out with the Reynolds numbers ranging from 2800 to 6200. Meanwhile, the effects of rotor diameters on heat transfer enhancement performance of the rotors were investigated. The results showed that the Nusselt number of the rotors inserted tube was about 60%-200% higher than that of the plain tube under the same Reynolds numbers condition; the friction factor of the rotors inserted tube was about 16%-32% higher than that of the plain tube; the PEC values were obtained between 1.56 and 2.79. In addition, the Nusselt number, friction factor and PEC values of the rotors inserted tube increased with the increasing rotor diameter. This was because larger diameters of the rotors contribute to a stronger effect of swirling and thinning the boundary layer.