本文研究了温度梯度对不同浓度水.酒精混合蒸气的Marangoni凝结的影响。搭建了具有高气密性的实验台,设计了凝结表面存在温差的实验块。在低于大气压力(31.2 kPa,47.4 kPa,84.5 kPa)的条件下,对8个浓度(0%~50%)混合蒸气进行了实验研究并实现可视化。实验结果表明温度梯度在低过冷度(<10K)下,提高了低浓度(0.5%,1%)的水-酒精混合蒸气的换热系数。分析认为是因为表面温差带来了表面张力的差异,促使液膜内扰动增大,减少了凝结液膜热阻的缘故。
The effect of temperature gradient on Marangoni condensation for different concentrations water-ethanol mixtures was presented experimentally.An experimental system with high leakage was built.An oblique block was designed to form temperature difference.The experiment was per- formed under difference pressures(31.2 kPa,47.4 kPa,84.5 kPa)and concentrations(0%~50%).The experimental results showed that temperature gradient improved heat transfer coefficient for low con- centration water-ethanol mixtures(0.5%,1...