摘要
为探究直接接触冷凝器内传热传质特性,针对R290直接接触冷凝制冷系统中R290过热蒸气与R290过冷液直接接触冷凝过程,提出了3种不同尺寸的筒型正交混合式冷凝器,采用Fluent软件对其进行了气液两相热质传递的数值模拟。结果发现:在相同冷凝工况下,体积较小的A型冷凝器内部流型为环状流,体积较大的B、C型冷凝器内部流型为泡状流;A型冷凝器内几乎不发生传热传质;在产生泡状流的冷凝器中,冷凝器体积越大,传热传质效果越好;冷凝器体积传热系数随体积增大而减小;在相同冷凝热负荷的情况下,直接接触冷凝器所需换热面积仅为间壁式冷凝器的8%~14%。研究结果可为直接接触冷凝器设计优化提供可行方案。
In order to explore the heat and mass transfer characteristics in the direct contact condenser,aiming at the direct contact condensation process of R290 superheated steam and R290 supercooled liquid in the R290 direct contact condensation refrigeration system,three kinds of cylindrical orthogonal hybrid condensers with different sizes are proposed.The numerical simulation of gas-liquid two-phase heat and mass transfer was carried out by using FLUENT software.It is found that under the same condensing condition,the internal flow pattern of smaller A-type condensers is annular flow,and the internal flow pattern of larger B-type and C-type condensers is bubble flow.There is almost no heat and mass transfer in A-type condenser.In the condenser producing bubble flow,the larger the condenser volume,the better the heat and mass transfer efficiency.The volumetric heat transfer coefficient of the condenser decreases with the volume increase.Under the same heat load and heat transfer temperature difference,the heat transfer area of direct contact condenser is only 8%to 14%of the heat transfer area of the surface heat condenser.The research results can provide a feasible scheme for the design optimization of direct contact condenser.
作者
宁静红
杨挺然
刘华阳
贾永勤
刘兴华
Ning Jinghong;Yang Tingran;Liu Huayang;Jia Yongqin;Liu Xinghua(Tianjin Key Laboratory of Refrigeration Technology,Tianjin University of Commerce,Tianjin 300134,China;Tianjin Tian Shang Cooling Technology Co.,Ltd.,Tianjin 300134,China)
出处
《绿色科技》
2023年第2期230-236,共7页
Journal of Green Science and Technology
基金
天津市自然科学基金项目(编号:18JCYBJC22200)。
关键词
直接接触
冷凝器
气液两相流
传热传质
direct contact condensation
condenser
gas-liquid two-phase flow
heat and mass transfer
作者简介
宁静红(1964-),女,博士,教授,研究方向为制冷系统的节能与优化。
