直接空冷凝汽器翅片管积灰流动换热的数值研究  

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

作　　者：张学镭[1] 孙苗青[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,保定071003

出　　处：《汽轮机技术》2016年第5期357-360,364,共5页Turbine Technology

基　　金：中央高校基本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流动换热特性,利用FLUENT软件数值模拟了翅片管外不同积灰厚度的流动换热情况,得到了夏季工况翅片管4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的变化曲线,非线性拟合得到了摩擦系数、努赛尔数与雷诺数之间的关联式。利用性能评价指标PEC,对翅片管束积灰前后的流动换热性能进行了比较。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;随着翅片管外积灰厚度的增加,对流换热系数、流动阻力以及摩擦系数变大,传热系数变小。In order to further study the heat transfer and flow characteristics of dust accumulation on direct air-cooled condenser cooling tubes, the heat transfer and flow of the different thickness of the fin tube are simulated by FLUENT software, the convective heat transfer coefficient, heat transfer coefficient and flow resistance of four kinds of thickness of the fin tubes in the summer working conditions are obtained, the nonlinear correlating equations of the friction factor versus Reynolds number, and the Nusseh number versus Reynolds number were fitted. By using the performance evaluation index P-c, the flow and heat transfer performance of the finned tube bundles were compared. The results show that the convective heat transfer coefficient, heat transfer coefficient, and flow resistance before and after the deposition of ash are gradually increased with the increase of the wind speed; with the increase of the thickness of the fin tube, the heat transfer coefficient, the flow resistance and the coefficient of friction become larger, and the heat transfer coefficient becomes smaller.

关 键 词：翅片管束 积灰厚度 流动换热特性 性能评价指标 

分 类 号：TK267[动力工程及工程热物理—动力机械及工程]