A decoupled method to identify affecting mechanism of crosswind on performance of a natural draft dry cooling tower

Abstract

The natural draft dry cooling tower (NDDCT) has been increasingly used for cooling in power generation in arid area. As crosswind affects the performance of a NDDCT in a complicated way, and the basic affecting mechanism is unclear, attempts have been made to improve the performance of a NDDCT based on limited experiences. This paper introduces a decoupled method to study the complicated crosswind effects on the inlet and outlet of a NDDCT separately by computational fluid dynamics (CFD) modeling and hot state experiments. Accordingly, the basic affecting mechanism of crosswind on the NDDCT performance is identified. Crosswind changes the inlet flow field of a NDDCT and induces mainstream vortices inside the tower, so as to degrade the ventilation. Besides, low crosswind deflects the upward plume at the outlet to further degrade the ventilation, while high crosswind induces the low pressure area at the outlet to reduce the ventilation degradation.

Keywords

affecting mechanism / crosswind / decoupled method / mainstream vortices / natural draft dry cooling tower (NDDCT) / degradation

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Acknowledgments

This research was supported by China Postdoctoral Science Foundation (No. 2017M620758), Special Funds of the National Natural Science Foundation of China (Grant No. L1522032), and the Consulting Project of Chinese Academy of Engineering (No. 2015-ZCQ-06).

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2020 Higher Education Press