在压力分别为31．16 kPa和47．5 kPa下,进行了酒精气相质量分数为0％、1％、5％,10％的凝结换热实验并观测了凝结形态,混合蒸气的质量流量为10 kg/h 和14 kg/h,实验圆管长度为150 mm,外径为16 mm,壁厚为3 mm,管外的换热系数通过 Gnielinski关联式计算.实验研究发现,混合蒸气的凝结形态为珠状凝结,混合蒸气的换热系数比同样实验条件的纯水蒸气都有不同程度的提高,尤其是1％浓度的混合蒸气.随着质量流量和压力的增大,换热系数有所提高,在当前的流量变化范围内,压力的影响更大一些.%An experimental loop has been established to measure the condensation heat transfer coefficient of ethanol-water mixed vapor in a tube,the pressures are 31.16 kPa and 47.16 kPa,the mass concentrations of ethanol vapor phase are 0%,1%,5% and 10%,vapor mass flux is 10 kg/h or 14 kg/h.The experimental tube has a length of 1 500 mm,outer diameter of 16 mm and a wall thickness of 3 mm.The heat transfer coefficient of outside of tube is acquired by Gnielinski correlation.The experiment shows that dropwise mode would appear mixed vapor condensing,for different concentration vapor,heat transfer coefficient increased in various degrees,especially for 1%.The HTC also increased a little with increase of mass flux and pressure,and the effect of pressure on HTC is greater compared to mass flux.
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