摘要
对R245fa水平光滑管管内流动沸腾换热特性进行了实验研究,主要包括加热水质量流速、工质质量流速、蒸发温度以及干度对局部换热系数的影响,结果表明在相同蒸发温度及加热水质量流速下,随着工质质量流速增大,管内流动沸腾换热系数迅速升高;在相同工质质量流速及蒸发温度下,随着加热水质量流速的增大,管内流动沸腾换热系数升高;在相同工质质量流速及加热水质量流速下,随着蒸发温度的升高,管内流动沸腾换热系数降低。分别采用Chen公式、Liu-Winterton公式、Shah公式计算了与本实验相同工况下R245fa的管内流动沸腾换热系数,其结果表明:3个预测公式的计算结果与实验值之间的平均误差分别为31.6%、6.3%、37.4%。采用Liu-Winterton公式计算R245fa的流动沸腾换热系数满足工程实际的要求。
Convective boiling heat transfer characteristics of R245fa inside horizontal tube are investigated at various mass flow rates of hot water,working fluids and at various evaporation temperatures.The investigation results show that convective boiling heat transfer coefficients goes up with the increase of hot water and working fluid mass flow rate,but it is contrary to evaporation temperature.By comparisons of the experimental local heat transfer coefficients with that predicted by Chen correlation,Liu-Winterton correlation and Shah correlation,it is concluded that deviations of these three correlations are 31.6%、6.3%、37.4% respectively.Liu-Winterton correlation is more precise to predict convective boiling heat transfer coefficients of R245fa than Chen correlation and Shah correlation.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2011年第3期67-71,共5页
Journal of Wuhan University of Technology
基金
国家自然科学联合基金重点项目(U0937604)
云南省自然科学重点基金资助项目(2008KA002)
关键词
流动沸腾换热
质量流速
蒸发温度
关联式
convective boiling heat transfer
mass flow rate
evaporation temperature
crrelation
