垂直布置B30波槽管管外膜状凝结的实验研究

Experimental Investigation of the Tube-outside Film-shaped Condensation in a Vertically Installed B30 Corrugated Tube

在略高于大气压的凝结条件下,对垂直布置波槽管管外膜状凝结换热进行了实验研究。实验结果表明:垂直布置时波槽管具有一定的强化传热效果,在实验范围内,最佳波槽管的总传热系数约比光管提高27%～43%,而阻力系数约为光管的2.94～3.48倍,垂直布置的强化传热效果不如水平布置的好。通过对实验数据的回归分析,得到了垂直管管内对流换热、管外凝结换热及阻力系数的实验关联式。

Under the condition of condensation at a pressure slightly higher than the atmospheric one an experimental investigation was conducted of the tube-outside film-shaped condensation heat exchange in a vertically installed corrugated tube. The results of the investigation indicate that the vertically installed corrugated tube enjoys definite heat-transfer intensification effectiveness. Within the range of the experiments the overall heat transfer factor of an optimum corrugated tube is higher than that of a bare tube by 27%-43%, while its resistance factor is about 2.94-3.48 times that of a bare tube. The heat transfer intensification effectiveness of a vertically installed tube is inferior to that of a horizontally installed one. Through a regressive analysis of the test data an experimental correlation formula was obtained for the following items of the vertical tube: the tube-inside convection heat exchange, the tube-outside condensation heat exchange and the resistance factor.