直接空冷凝汽器翅片管积灰的换热特性研究  

Study on Heat Transfer Characteristics of Dust Accumulation on Direct Air-cooled Condenser Fin

作　　者：张学镭[1] 孙苗青[1] 葛永建[1] 段俊阳[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《电力科学与工程》2016年第3期59-66,共8页Electric Power Science and Engineering

基　　金：中央高校基金科研业务费专项资金资助(2015MS116)

摘　　要：为了深入研究空冷凝汽器散热管束积灰时的传热与流动特性,利用FLUENT软件数值模拟了翅片管束不同积灰厚度的传热及流动情况,对比分析了翅片管束不同积灰厚度的压力分布、温度分布及速度分布,计算得到了翅片管束5种积灰厚度的对流换热系数、传热系数及流动阻力随迎面风速变化的规律,拟合得到了摩擦系数及努塞尔数随雷诺数变化的关系。结果表明:随着迎面风速的增加,积灰前后的管外对流换热系数、传热系数以及流动阻力逐渐增加;同一迎面风速下,随积灰厚度的增加,对流换热系数和流动阻力增大,传热系数减小。In order to study the heat transfer and its flow characteristics of dust accumulation on direct air-cooled condenser cooling tubes, the heat transfer and flow condition of the different thickness of the fin tube were simula- ted by FLUENT software, and the distribution of the pressure, temperature and velocity of different thickness of the fin tube were compared and analyzed. The variations of the convective heat transfer coefficient, heat transfer coeffi- cient and flow resistance of the five kinds of ash deposits with the windward velocity were presented, and the correlating equations of the friction factor versus Reynolds number and the Nusseh number versus Reynolds number were obtained by fitting. The results show that the convective heat transfer coefficient, heat transfer coefficient, and flow resistance before and after the deposition of ash grow gradually with the increase of the wind speed. Under the same windward velocity, convective heat transfer coefficient and flow resistance are enhanced and heat transfer coefficient drops with the increase of the thickness of the ash.

关 键 词：蛇形翅片扁平管 迎面风速 积灰厚度 流动换热特性 

分 类 号：TK267[动力工程及工程热物理—动力机械及工程]