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研究火电站空冷凝汽器广泛采用的波形翅片扁平管管束外空气流动传热特性,对于火电站空冷岛的设计与运行都具有重要意义。该文通过CFD模拟,得到不同空冷凝汽器迎面风速条件下冷却空气的流场和温度场,通过计算获得了空冷凝汽器冷却空气平均对流换热系数和摩擦系数随翅片间距和翅片高度的变化规律。结果表明:随空冷凝汽器迎面风速增加,空气对流换热增强,摩擦系数降低。对每个迎面风速而言,都存在一个最佳翅片间距,对流换热最强。翅片高度增加,对流换热系数和摩擦系数减小。对空冷凝汽器波形翅片管束空气流动传热性能综合评价指标的分析表明,最佳翅片间距和高度需要通过综合技术经济比较确定。
It is important for the design and operation of the air-cooled island of thermal power plant to study the heat transfer characteristics of air flow outside the flattened fin tube with corrugated fins widely used in the air-cooled condenser of thermal power plant. Through the CFD simulation, the flow field and the temperature field of the cooling air under different front-end air-cooling conditions are obtained. The average convective heat transfer coefficient and friction coefficient of the cooling air of the air-cooled condenser are calculated with the fin pitch and the fin The height of the law of change. The results show that the air convection heat transfer increases and the friction coefficient decreases as the head-on wind speed of the air-cooled condenser increases. For each oncoming wind speed, there is a best fin spacing, the strongest convection heat transfer. The fin height increases, the convection heat transfer coefficient and the friction coefficient decrease. Air-cooled condenser finned finned tube bundle air flow and heat transfer performance evaluation index analysis showed that the best fin spacing and height need to be determined by comprehensive technical and economic comparison.