水-酒精混合蒸气在板式换热器中凝结时的压降特性  

Pressure Drop in Plate Heat Exchanger During Condensation of Ethanol-Water Mixed Vapor

作　　者：乔宏斌[1] 王顺[1] 胡申华[1] 

机构地区：[1]南京工程学院电力仿真与控制工程中心,南京211167

出　　处：《动力工程学报》2017年第1期33-38,共6页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(51166013);南京工程学院校级科研基金资助项目(YKJ201533)

摘　　要：通过设计搭建板式换热器凝结换热实验台,研究了不同酒精质量分数(0%、1%、10%和50%)、蒸气压力(70kPa、80kPa和90kPa)和蒸气流速(15m/s和25m/s)下,水-酒精混合蒸气在板式换热器中凝结时的热侧压降随出口蒸气干度的变化特性.在实验数据的基础上,采用Lockhart-Martinelli模型计算压降,并对其进行修正.结果表明:压降随着酒精质量分数的增大而升高,与纯水蒸气相比,在同样工况下,50%酒精质量分数的混合蒸气压降增大近1倍;在相同的酒精质量分数、蒸气流速和出口蒸气干度下,蒸气压力对压降影响明显,蒸气压力越大压降越小;实验值与拟合值的对比误差在±20%.Experimental tests were carried out in a plate heat exchanger to study the effects of outlet vapor quality on the changes of hot side pressure drop during condensation of ethanol water mixed vapor at different ethanol mass fractions （0%, 1%, 10% and 50%）, different vapor pressures （70 kPa, 80 kPa and 90 kPa）, and different vapor flow rates （15 m/s and 25 m/s）. Based on the experimental data, the Lockhart- Martinelli model was used to calculate and correct the pressure drop. Results show that the pressure drop increases with the rise of ethanol mass fraction, which would be doubled for the mixed vapor with ethanol mass fraction of 50% as compared to pure water vapor, under same experimental conditions. Under condi- tions with the same ethanol concentration, vapor flow rate and outlet vapor quality, the vapor pressure has obvious effects on the pressure drop; the higher the vapor pressure is, the smaller the pressure drop will be. The error between experimental data and fitted results is within 20 %.

关 键 词：混合蒸气 板式换热器 凝结 压降 传热 

分 类 号：TK121[动力工程及工程热物理—工程热物理]