摘要
通过数值模拟分析了某台300MW机组直接空冷凝汽器冷凝单元的流场及散热情况,以无风和风速3、5m/s为例,研究环境背风对空冷凝汽器的影响。结果表明,流经冷凝单元两侧的气流温度较高,A型架内侧底部4个角区有强列的涡流,散热效果不明显;环境背风会导致较强的热风回流,极大地降低换热性能,并且换热性能的降低与高大建筑物所引起的绕流效应关系密切。无风和风速为3、5m/s时的总换热量分别为807、516、540MW,说明在环境背风风速不高的情况下,略提高风速,换热性能有较小提高。
Flow field and heat dissipation situation of the condensate unit on a direct air - cooling con- denser for a 300 MW unit was simulated. To study the adverse effect of environmental leeward on air- cooled condenser,wind speed at 0 m/s,3 m/s,5 m/s were taken as examples respectively. Results show that, the temperature of air flowing through the condensate unit is higher,inside the A- shape shelf, at the bottom 4 corners,there＇s strong vortex,and heat dissipation is not obvious. The heat transfer per- formance will be reduced extremly because of the strong hot air reflow caused by environmental lee- ward, that is closely related with the flow around effect resulted from tall buildings. The total heat ex- change amount was 807 MW,516 MW and 540 MW when the wind speed was as mentioned 0 m/s, 3 m/s and 5 m/s,respectively,this indicates that,when the environmental leeward flow rate is not very high,slightly increasing the wind speed can improve the heat transfer performance a bit.
出处
《热力发电》
CAS
北大核心
2012年第5期50-55,共6页
Thermal Power Generation
基金
国家科技支撑计划项目(2009BAA16B00)
黑龙江省杰出青年科学基金资助项目(JC200912)
关键词
300MW机组
直接空冷凝汽器
环境背风
热风回流
绕流
300 MW unit
direct air- cooled condenser
environmental leeward
hot air reflow
flow around
