摘要
沸腾换热装置广泛存在于石油、化工等工业领域中。目前针对临界热负荷预测模型中环状流初始夹带份额的假设缺乏理论依据。基于搅拌流内相关实验结果和理论认识,系统分析初始夹带份额对临界热负荷预测精度的影响。结果表明:搅拌流区内夹带液滴尺寸较大且具有较大的动量,对下游环状流流场特征产生较大的影响,特别是当质量流量较高时,初始夹带份额的选取对临界热负荷预测精度、出口干度影响剧烈。因此,文章提出了将临界热负荷预测模型的计算起始点由环状流起始点提前至搅拌流起始点的改进思想。改进后的液膜流动模型不仅预测精度较高,且更符合实际物理过程。
Boiling heat exchangers are widely used in petroleum,chemical and other industrial fields.However,the current assumption of the onset entrainment fraction of annular flow in the model for critical heat flux lacks theoretical basis.Based on the relevant experimental results and theoretical understanding of churn flow,the effects of the onset entrainment fraction on the accuracy of critical thermal load prediction is analyzed systematically.The results indicate that the larger droplet size and larger momentum within the churn flow zone have a greater impact on the downstream annular flow field characteristics,especially when the mass flow rate is higher,the selection of the onset entrainment fraction has a drastic effect on the critical heat load prediction accuracy and outlet dryness.Therefore,this paper proposes the improvement idea of advancing the onset calculation of the critical heat load prediction model from the onset of annular flow to that of the churn flow.The improved liquid film flow model not only provides higher prediction accuracy,but also is more in accord with the actual physical process.
作者
林睿南
王昊
安建川
肖飞
王科
Lin Ruinan;Wang Hao;An Jianchuan;Xiao Fei;Wang Ke(Gas Management Office of PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan,610213;China University of Petroleum-Beijing,Beijing,102249;Geological Expolration&Development Research Institute of CNPC Chuanqing Drilling Engineering Co.Ltd.,Chengdu,Sichuan,610051)
出处
《石油化工设备技术》
CAS
2021年第6期5-10,I0001,I0002,共8页
Petrochemical Equipment Technology
基金
中石油科研开发项目:60125-CA-ESC-001
中国石油大学(北京)科研基金(2462020XKJS01,ZX20200126)。
关键词
搅拌流
液膜流动模型
临界热负荷
液滴夹带
churn flow
liquid film flow model
critical thermal load
droplet entrainment
