钛波槽管水平管外凝结换热的实验研究

Investigation of condensation heat transfer of horizontal titanium circular-grooved tube

在常压条件下，对水平钛波槽管管外凝结换热及流阻特性进行了实验研究．在实验参数范围内，5号波槽管的总传热系数为光管的1．54～1．64倍，而管内水阻约为光管的3．39～4．42倍．通过对实验数据的回归分析，得到了管内对流换热、管外凝结换热及阻力系数的实验关联式．在管径及壁厚一定的条件下，波槽管的节距和槽深有一个最佳组合．根据实验结果，推荐最佳结构参数为φ=0，00135～0．003606．结果表明，钛波槽管是实现船用冷凝器小型化较为理摁的强化管管型．

Experimental investigation of heat transfer and friction characteristics was conducted on the outside of a horizontal titanium circular-grooved tube under atmospheric pressure. Within the experimental region, the total heat transfer coefficient and resistance of the circular-grooved tube are 1.54 ～ 1.64 times and 3.39 ～ 4.42 times respectively, compared with a smooth tube. Based on experimental data, empirical correlations for the inside heat transfer coefficient and friction factor and the condensation heat transfer coefficient of film condensation were achieved in terms of regression. When the diameter and thickness of the tube are fixed, there is an optimal combination for pitch and depth of groove. Based on the experimental results, the optimal structure parameter of a circular-grooved tube is φ = 0. 001 35～0. 003 606. Experiments indicate that a titanium circular-grooved tube is a better choice for heat transfer enhancement required for the miniaturization of naval steam condensers.