直接空冷系统椭圆翅片管管束传热与流动性能的数值分析

直接空冷系统的空冷元件中,大口径热浸锌椭圆钢管绕椭圆翅片管因其具有空气侧流动阻力较小、换热系数较高、使用寿命长、清洗效果好、技术成熟等优点,在西北地区直接空冷机组中广泛应用。本研究采用CFD技术对三排管直接空冷凝汽器空气侧流动及换热性能进行细致分析,讨论了不同迎面风速下的三排管空冷翅片间的压力、速度和温度分布特性。结果表明,随着迎面风速的增加使换热系数增大,阻力增大;后排管的换热较前排管弱。本文模拟的结果可为空冷凝汽器的优化设计提供参考依据。

Numerical Stimulation of the Heat Transfer and Flowing Property of Triple Row Tube Bundle

In the Direct Air Coohng Units （DACC）, the helically wound galvanized steel finned elliptical triple row tube of the air- cooled Condenser is widely used in the northwest distrit due to many advantages, such＂ as low flow resistance, high heat transfer coefficient , long service life and satisfactory cleaning＇effect. The flow and heat transfer characteristic in triple row tube is analyzed by using CFD technology.The flow field and temperature field were discussed under different frontal wind velocities. The result indicates that with the increasing of frontal wind velocities, both of the heat transfer coefficient and resistance increases, and with the tube row increases, the heat transfer performance is weaken, which can provides a reference for the optimization and design of air- cooled Condenser.