Influence of Ambient Velocity on the Performance of SCAL Indirect Air-Cooled Towers

环境风速对 SCAL 型间接空冷塔性能的影响

Received: 6 May 2017

Abstract

In order to explore the influence mechanisms of ambient wind speed on the performance of indirect air-cooled system, SCAL indirect air-cooled towers of a 600MW supercritical unit was taken as an example, and the corresponding calculation model was established. By the ways of CFD numerical simulation and field test, the variations along with ambient velocity of airflow field inside and outside the tower were simulated and the thermal performance of those towers under different ambient velocity was studied. The results showed that, the outlet resistance of air-cooled tower increased in pace with ambient velocity. Both temperature field inside the tower and pressure field inside and outside the tower were influenced by the ambient velocity to a large extent, while flow trajectory of flue gas inside the tower was basically similar. Moreover, the trends and changing laws of performance parameters from the level of segments and the tower were achieved. The conclusions would be of some reference significance for the optimal operation and design of indirect air-cooled system.

摘要

为探究环境风速对间接空冷系统性能影响机理，以某600 MW超临界机组SCAL空冷塔为对象，建立相应的计算模型，采用CFD数值模拟与现场试验相结合的方式，模拟了空冷塔内、外流场随环境风速的变化情况，研究了不同环境风速下空冷塔的热力性能。结果表明，随着环境风速的增加，空冷塔出口阻力增大，塔内温度场、塔内外压力场受风速影响较大，塔内烟气流动轨迹基本保持相似；并得到了各扇段及塔整体性能参数随环境风速的变化趋势和规律，为间接空冷系统的运行和设计提供一定的参考。