直接空冷凝汽器管束冻结规律与流量控制研究

Freezing Regularity and Flow Control Research on Direct Air-Cooled Condenser Tubes

以直接空冷机组凝汽器单排蛇形翅片管为研究对象,建立了管内流体流动换热过程的数学模型,利用Fluent软件,对翅片管内凝结水的流动状态进行了模拟,总结了单排蛇形翅片管的冻结规律。并以300 MW直接空冷机组为例,分析了机组在冬季低温环境下运行时迎面风速、环境温度及负荷对管内凝结水冻结的影响;提出了在保证机组安全经济性前提下的单排管内蒸汽流量的最佳控制范围,为直接空冷系统的冬季防冻运行提供理论参考。

By analyzing the direct air-cooled unit single row serpentine finned tubes,established the mathematical model of fluid flow and heat transfer process in tubes,analyzed theoretically the flow process of steam in the finned tube and deduced frozen law of condensation water in the tube of air-cooled condenser unit.Using Fluent software,established a finned tube model and analyzed the condensate flow state within the finned tubes.Taking a 300 MW direct air-cooled unit as an example,obtained the freezing law of condensation water in inner tubes in the winter cold operation state under different wind face velocity,ambient temperature and the working load.And in ensuring the safety and economy of the premise,proposed the best range of steam flow in the tube to provide a reference for the winter run of direct air-cooled system.