双排管直接空冷换热元件性能试验研究

Experimental investigation on performance of direct air-cooled heat exchanger elements of double-row tubes

空冷凝汽器散热器的结构是影响其性能的关键。对此,以2个不同结构尺寸的双排管直接空冷换热元件(换热元件)为例,对其热力性能进行试验研究。结果表明:随着迎面风速的增加,换热元件的传热系数及空气阻力均逐渐增大,其中传热系数的增加幅度逐渐减小,空气阻力的增加幅度逐渐增大;当迎面风速小于2m/s时,2个换热元件的换热系数基本相同;当迎面风速大于2m/s时,翅片尺寸较小的换热元件的传热系数明显大于翅片尺寸较大的换热元件,且随着迎面风速的增大,两者的差别逐渐增大;实际工程中,应对迎面风速、翅片尺寸及翅化比进行优化,以提高空冷凝汽器的热力性能。

The radiator＇s structure affects performance of the air cooling condensers to a great extent. Thus, two direct air cooling heat exchanger elements of double-row tubes with different fine types were taking as the example to conduct performance experiments. The results show that, with an increase in face velocity, both the heat transfer coefficient of heat exchanger components and the air resistance increase gradually, while the growth rate of heat transfer coefficient decreases and that of the air resistance rises. When the face velocity is lower than 2 m/s,the heat transfer coefficients of the two elements are basically the same. While when the face velocity is higher than 2 m/s,the heat transfer coefficient of the element with large fin size is obviously greater than that with small fin size, and the difference between them increases with the face velocity. In practical application, the face velocity, fin size and finned ratio should be optimized to enhance the thermal performance of air cooling condensers.