CO_2/丙烷混合工质管内流动沸腾换热的数值模拟  

Numerical Simulation on Flow Boiling Heat Transfer of CO_2/Propane Mixture in Tubes With/Without Micro-Fins

作　　者：吴晓敏[1] 魏兆福[1] 莫少嘉[1] 姜培学[1] 王维城[1] 

机构地区：[1]清华大学热能工程系热科学与动力工程教育部重点实验室,北京100084

出　　处：《工程热物理学报》2011年第6期1019-1022,共4页Journal of Engineering Thermophysics

基　　金：国家863计划(No.2006AA05Z416);国家973计划(No.2010CB227305)

摘　　要：通过在FLURENT软件中植入相变UDF模块,实现了对混合工质流动沸腾换热的数值模拟。模拟对象为质量比50/50的CO_2/丙烷混合工质在内径4 mm长1.4 m的光管和微肋管内的流动沸腾换热,工况如下,入口流速为0.487 m/s、入口温度为-5℃、操作压力为2.0928 MPa、壁面热流密度为100 kW/m^2。对比分析了两管内工质的速度分布、温度分布、液相容积分布和流动沸腾换热系数。结果表明,相对于光管,微肋管内工质由于微肋的作用,流速更大,温度更高,气液相分界面出现更早,对流换热系数更大,即微肋管内CO_2/丙烷混合工质的沸腾换热被强化。In this paper,a phase transition UDF module was embedded into the FLURENT to achieve the numerical simulation of flow boiling heat transfer characteristics.The object is CO_2/propane （50/50）mixtures in horizontal smooth and micro-fin tubes with ID of 4 mm and length of 1.4 m. The simulation were conducted at inlet velocity of 0.487 m/s,inlet fluid temperatures of-5℃, pressure of 2.0928 MPa and heat flux of 100 kW/m^2.The velocity distribution,the temperature distribution,the liquid volume fraction distribution and the heat transfer coefficient of CO_2/propane were investigated.The results showed that,compared with the smooth tube,CO_2/propane in the micro-fin tube had larger flow velocity,higher temperature,earlier boiling,and greater heat transfer coefficient.Thus boiling heat transfer of CO_2/propane in the micro-fin tube was enhanced.

关 键 词：CO_2/丙烷混合工质 流动沸腾 强化传热 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理]