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在搭建圆管混合蒸气凝结换热实验台的基础上,在圆管外进行了一系列不同气相浓度酒精和水混合蒸气的Marangoni凝结实验。在实验过程中进行了可视化研究并拍摄了大量的凝结图片,研究了酒精蒸气浓度对传热系数的影响及冷却水流量对壁面温度的影响.实验结果表明,传热系数随酒精浓度的提高而降低,酒精浓度为1%时传热系数达到最高值,换热系数比相同工况下纯水蒸气提高近30%.最后,对传热系数随浓度的变化做了定性分析。
On the basis of setting up the experimental tube of steam tube condensation and condensation heat transfer, a series of Marangoni condensation experiments were carried out outside the tube with alcohol and water vapor of different gas phase concentrations. During the experiment, a large number of condensation images were taken and the effects of alcohol vapor concentration on the heat transfer coefficient and cooling water flow on the wall temperature were studied.Experimental results show that the heat transfer coefficient increases with the increase of alcohol concentration The heat transfer coefficient reached the highest value when the alcohol concentration was 1%, and the heat transfer coefficient increased by nearly 30% compared with the pure water vapor under the same working condition.Finally, the qualitative analysis of the heat transfer coefficient with the concentration was made.