空冷凝汽器蛇形翅片扁平管空气侧流动与换热特性研究

Study on The Air-side Flow and Heat Transfer Characteristic of Wave-finned Flat Tube in Air-cooling Condensers

针对应用于电站直接空冷凝汽器的蛇形翅片扁平单排管,对其空气侧的流动及换热特性进行了数值模拟。给出了该管件基本结构的雷诺数和欧拉数随迎面风速的变化关联式;结果显示,同一迎面风速下,随着翅片间距、高度的增大,换热变差,流动变好。但当间距增加到一定程度时,风速与间距对换热流动性能的影响都变得很小。风速越大,换热性能对翅片间距、高度越敏感,而流动则相反,需根据实际工况来选择合适的翅片间距及高度。

The air-side flow and heat transfer characteristic of single row wave-finned flat tube which is applied in direct air-cooling condensers in power station are investigated numerically. And the results show that the bigger velocity, the better heat transfer performance and the worse flow performance. As the fin pitch and height go larger at the same velocity, heat transfer coefficient of the air-side and flow friction go smaller. But the air velocity and the fin pitch can barely influence flow and heat transfer performance when the pitch is too big. The fin pitch and height should be determined according to working conditions.