不锈钢纵槽管降膜蒸发传热性能

Heat Transfer Performance of Falling Film Evaporation on Stainless Steel Vertical Fluted Tubes

降膜蒸发是一种高效传热方式。以水为实验工质,对不锈钢纵槽管降膜蒸发传热性能进行了实验研究。在热通量q=13.2~56.52 kW/m^2,液体周边进料流量Γ=0.419~1.112 kg/(m·s),传热温差ΔT=2.02~9.87℃下测量纵槽管传热系数;并与相同操作条件下的光管传热系数进行比较。结果表明:纵槽管强化传热效果在一定范围内随着管内雷诺数增大而增大;在热通量相同时,纵槽管的传热温差仅为光管的51%;纵槽管管外冷凝传热系数为光管的2.07倍,总传热系数为光管的1.73倍,强化效果显著。

Falling film evaporation is high-performance heat transfer method.The experimental study on the heat transfer performance of the falling film evaporation on stainless steel fluted tubes is carried out by using water as the working fluid.The heat transfer coefficients of fluted tubes were calculated with heat flux from 13.2 kW/m2 to 56.52 kW/m, liquid peripheral feed flow from 0.419 kg/（m＆#183;s） to 1.112 kg/（m＆#183;s）, heat transfer temperature difference from 2.02 ℃ to 9.87 ℃, and compared heat transfer coefficients to smooth tubes under the same operation conditions.The results show that the heat transfer enhancement of fluted tubes increases with the increase of Reynolds number in certain range;in the same heat flux, the heat transfer temperature difference of the fluted tube are only 51% compared with smooth tube;the condensation heat transfer coefficients of fluted tube are 2.07 times that of smooth tube, and the overall heat transfer coefficients are 1.73 times, the enhancement effects are remarkable.