平直翅片换热器空气侧换热与阻力特性研究  

Study on Air Side Heat Transfer and Resistance Characteristics of Straight Fin Heat Exchanger

作　　者：丛晓春[1] 倪鹏飞 王庆刚 景洲 CONG Xiao-chun;NI Peng-fei;WANG Qing-gang;JING Zhou(Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation,Shandong University of Science and Technology,Qingdao,China,266590)

机构地区：[1]山东科技大学土木工程防灾减灾重点实验室,山东青岛266590

出　　处：《热能动力工程》2020年第5期78-86,共9页Journal of Engineering for Thermal Energy and Power

摘　　要：以平直翅片管式换热器为研究对象,利用计算流体力学(CFD)软件进行流动与传热模拟计算。采用正交试验方法确定模型工况,对换热负荷15 kW,设计气温30℃,入口风速为1~5 m/s,管壁温度为40~60℃,翅片间距为1~5mm、翅片厚度0.5~4 mm、管纵向间距为0.5~2.5倍外管径,管排数为1~5排的计算工况进行努塞尔数、阻力因子的计算分析。参数敏感性分析结果表明:在1 mm≤翅片间距δ≤5 mm,444≤雷诺数Re≤3405时,翅片间距δ是对努塞尔数Nu及阻力因子f影响最大的结构参数。在该范围内提出了由翅片间距与特征长度比值组成的无量纲参数对努塞尔数Nu与阻力因子f的计算关联式。该关联式参数图表明:翅片间距δ越小、雷诺数Re越大,对提高平直翅片努塞尔数、降低阻力因子越有利。With a flat finned tube heat exchanger as the research object,the flow and heat transfer simulation calculations are carried out by using computational fluid dynamics(CFD)in this paper.The orthogonal test method is used to determine the working conditions,and the Nusselt number and resistance factor are calculated and analyzed for thoses with 15 kW heat exchange load,30℃design temperature,1~5 m/s wind speed at the inlet,40~60℃tube wall temperature,1~5 mm the fin spacing,0.5~4 mm the fin thickness,and the tube spacing in 0.5~2.5 times of the outer diameter along longitudinal direction and 1~5 row number.Then,the sensitivity analyses on Nusselt number and resistance factor are performed.The results show that the fin spacingδ,as a structural parameter,has the greatest influence on the Nusselt number and the resistance factor.Then,the computational correlation of the ratio of fin spacing against feature length on heat transfer and flow resistance is put forward under the condition of 1 mm≤fin spacingδ≤5 mm and 444≤Reynolds number Re≤3405.The correlation parameter plot indicates the smaller the fin spacingδand the larger the Reynolds number Re,the more favorable the heat transfer and resistance to the flat fins.

关 键 词：平直翅片 正交试验 敏感性分析 换热特性 拟合公式 

分 类 号：TK124[动力工程及工程热物理—工程热物理]