纯蒸汽在竖直管内非完全冷凝换热特性的实验研究  

Experimental Study on Heat Transfer Characteristics of Pure Steam with Incomplete Condensation in Vertical Tube

作　　者：刘佳宝 曹夏昕[1] 杨培勋 Liu Jiabao;Cao Xiaxin;Yang Peixun(Heilongjiang Provincial Key Laboratory of Nuclear Power System&Equipment,Harbin Engineering University,Harbin,150001,China)

机构地区：[1]哈尔滨工程大学黑龙江省核动力装置性能与设备重点实验室,哈尔滨150001

出　　处：《核动力工程》2024年第2期72-81,共10页Nuclear Power Engineering

基　　金：国家自然科学基金(11975085)。

摘　　要：为研究纯蒸汽在竖直管内非完全冷凝的换热特性,使用内径为25 mm的换热管进行实验,入口压力为0.1~0.3 MPa,蒸汽质量流速为12~70 kg/(m^(2)·s)。研究了入口压力、质量流速和质量含气率对管内平均和局部冷凝换热系数的影响,判别了冷凝过程中液膜流态,分析了液膜湍流度和液滴夹带对竖直管内冷凝换热的影响。结果表明:冷凝换热系数随着质量流速和质量含气率的增大而增大,竖直管的冷凝换热系数随着入口压力的升高而降低。实验中的液膜流型主要在过渡流区间,液滴夹带的发生使局部冷凝换热系数提高。对比4种环状流冷凝换热关系式计算结果发现,Shah的经验关系式基本偏差在±30%以内,平均绝对偏差(MAD)为18.91%。基于实验数据提出的经验关系式,其计算值和实验值基本偏差在±10%以内。In order to study the heat transfer characteristics of pure steam with incomplete condensation in a vertical tube,an experiment was carried out using a heat exchange tube with an inner diameter of 25 mm,with an inlet pressure of 0.1~0.3 MPa and a steam mass flux of 12~70 kg/(m^(2)·s).The effects of inlet pressure,mass flux and mass quality on the average and local condensation heat transfer coefficients in the tube were investigated.The liquid film flow pattern in the condensation process was identified,and the effects of liquid film turbulence and droplet entrainment on the condensation heat transfer in the tube were analyzed.It is shown that the condensation heat transfer coefficient increases with the increase of mass flux and mass quality.However,the condensation heat transfer coefficient of vertical tube decreases with the increase of inlet pressure.The liquid film flow pattern in the experiment is mainly in the transition flow region,and the occurrence of droplet entrainment increases the local condensation heat transfer coefficient.Four annular flow condensation heat transfer equations are compared.The results show that the basic deviation of Shah's empirical equation is within±30%,and the mean absolute deviation(MAD)was 18.91%.An empirical correlation based on the experimental data is developed,and the basic deviation between the calculated value and the experimental value is within±10%.

关 键 词：竖直管 纯蒸汽 非完全冷凝 膜状凝结 环状流 冷凝换热系数 

分 类 号：TL332[核科学技术—核技术及应用]