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本文研究了蒸汽压力对水-酒精混合蒸汽竖直平板表面凝结换热特性的影响．搭建了具有高气密性的Marangoni凝结换热实验台,分别针对不同压力(31．16 kPa,47．36 kPa,84．53 kPa)、不同表面过冷度(表面过冷度范围2-32℃)的纯水、水-酒精混合液(气相酒精质量百分比浓度为2．28％,5．1％,51％)和酒精进行了换热特性的实验研究,实验结果表明混合蒸汽在相同流速和浓度下凝结表面传热系数随压力的升高而升高,分析认为这是因为相平衡压力的提高会导致凝结液量增加和凝结液平均温度提高,而使凝结汽液界面的表面张力提高,进一步增强了Marangoni效应的影响,从而使凝结表面传热得到加强．
In this paper, the effect of steam pressure on the condensation heat transfer characteristics of water-alcohol mixed vapor vertical slab was studied. A Marangoni condensing heat transfer experiment bench with high gas-tightness was set up, and the effects of different pressures (31.16 kPa, 47.36 kPa, 84.53 kPa), different supercooling degrees (supercooling range 2-32 ℃), water-alcohol mixture (mass percent concentration of gaseous alcohol is 2.28%, 5.1%, 51%) and alcohol were studied. The experimental results show that the mixed steam at the same flow rate And the concentration of the condensation surface heat transfer coefficient increases with the pressure increased, the analysis is that this is because the phase equilibrium pressure will lead to an increase in the amount of condensate and condensate average temperature, leaving the condensation of the vapor-liquid interface surface tension increased , Further enhancing the effect of the Marangoni effect so that heat transfer on the condensing surface is enhanced.