1 000 MW直接空冷发电机组凝汽器传热性能试验研究

Experimental Research on Heat Transfer Performance of Condenser Used in 1 000 MW Direct Air-cooled Generator Unit

不同工况下空冷凝汽器的换热性能,是火电直接空冷机组设计、优化和运行的主要依据。针对实际运行的1 000 MW超超临界直接空冷机组,对其凝汽器进行了夏季、冬季和秋季工况的试验研究。试验获得了夏季和冬季工况下凝汽器翅片管束迎面风速的分布和壁面温度的分布,发现翅片管束迎面风速分布从上至下逐渐增高,而管束壁面温度分布对于顺流单元从上至下逐渐降低,对于逆流单元从上至下逐渐增高;获得了顺流翅片管束的易结冻区域;获得了秋季工况下1 000 MW空冷机组空冷凝汽器空气侧努赛尔数和雷诺数之间的无量纲关联式。

Heat transfer performance of the air-cooled condenser（ACC） under various operating conditions is the main basis for design, optimization and operation of a direct air-cooled power plant. Experimental studies on the heat transfer performance of the ACC in a 1 000 MW ultra supercritical direct air-cooled power plant were carried out under the summer, autumn and winter conditions. The head-wind velocity and the surface temperature distributions on the finned-tube bundles were measured. It was found that the head-wind velocities increase from the top to the bottom inside air-cooled cells, and the surface temperatures decrease from the top to the bottom on the finned-tube bundles in down-flow air-cooled cells, but contrary in up-flow cells;The areas easy to freeze of ACC were found;Based on the experimental datum, a dimensionless correlation between Nusselt number and Reynolds number for the air side of the 1 000 MW ACC under autumn condition was derived.