旋流片支撑管束的传热与流阻性能

提出旋流网板管壳式换热器，并对空气纵向流过旋流片支撑光滑传热管束的传热与流阻性能进行了实验研究。另外比较了270-38.1、180-38.1、270-20.3、180-20.3 四种旋流片和空心环的强化传热性能。实验结果表明，270-20.3和180-20.3旋流片支撑光滑管束的强化传热评价因子η比空心环支撑的高出7％，而270-38.1、180-38.1、空心环的评价因子η相差不大。除了起到支撑管束作用外，270-20.3和180-20.3旋流片还具有良好的强化传热效果。实验结果可为对管壳式换热器的研究设计提供参考。

Heat transfer and flow resistance characteristics of tube bundle supported by twisted-leaves

A new type of shell-and-tube exchanger with twisted-leaf-net support was proposed, and the heat transfer and flow resistance characteristics in the tube bundle supported by twisted-leaves for air flow in the longitudinal direction were investigated.In addition, the heat transfer enhancement of twisted-leaf 270-38.1(a type of twisted-leaf with twist angle α=270° and swirl angle β=45°), 180-38.1, 270-20.3, 180-20.3 and ring support was compared with each other.The results indicated that the comprehensive evaluation factor η of heat transfer enhancement of twisted-leaves 270-20.3 and 180-20.3 was increased by about 7% against that of the ring support, while the factor η of twisted-leaves 270-38.1 and 180-38.1 was close to that of the ring support for Reynolds number (2.5×103～2.0×104).Besides supporting the tube bundle, the twisted-leaves of 270-20.3 and 180-20.3 enhanced heat transfer obviously.The results could be used as a reference in the further research and design of the shell-and-tube exchanger.