论文部分内容阅读
以某1 000MW直接空冷机组为例,对机组散热器外部流场进行了数值模拟,分析了不同迎面风速、环境温度、翅片间距以及翅片厚度对散热器外部换热和流动特性的影响.结果表明:随着迎面风速的增大,散热器外部的传热系数和流动阻力均显著增大,环境温度对散热器外部换热和流动特性的影响并不明显,但对总散热量影响较大;较大的翅片间距能增大散热器外部的传热系数、减小流动阻力,但会使单位管长的换热面积减小,总散热量减小;对应于一定的迎面风速,存在较为合理的翅片间距和翅片厚度,迎面风速越大,合理的翅片间距越大,翅片厚度越小.
Taking a 1 000 MW direct air-cooled unit as an example, the external flow field of the unit radiator was numerically simulated. The effects of different on-head wind speed, ambient temperature, fin spacing and fin thickness on the heat transfer and flow characteristics of the exterior of the radiator were analyzed. The results show that with the increase of oncoming wind speed, the heat transfer coefficient and flow resistance outside the radiator increase significantly. The influence of ambient temperature on the heat transfer and flow characteristics of the radiator is not obvious. The larger the fin spacing can increase the heat transfer coefficient outside the radiator to reduce the flow resistance, but will make the unit tube length of the heat transfer area decreases, the total heat dissipation decreases; corresponding to a certain oncoming wind speed, There is a more reasonable spacing between the fins and the thickness of the fins. The larger the facing wind speed, the larger the reasonable fin spacing, the smaller the thickness of the fins.