THERMAL SCIENCE

International Scientific Journal

Weiliang Wang

,

Junfu Lyu

,

Hai Zhang

,

Qing Liu

,

Guangxi Yue

,

Weidou Ni

UTILIZATION OF THE LATERAL ACCELERATED CROSS-WIND TO IMPROVE THE COOLING PERFORMANCE OF A NATURAL DRAFT DRY COOLING TOWER

ABSTRACT
Cross-wind degrades the performance of a natural draft dry cooling tower (NDDCT). Based on the basic affecting mechanism, this paper introduces a wind collecting approach. By using a wind collecting duct, the lateral flow acceleration of cross-wind is broken up, and the lateral flow kinetic energy is utilized to increase the lateral and rearward static pressure outside the radiator inlet. By adoption of a CFD model, the effect of the wind collecting approach is investigated comprehensively. It is found that the wind collecting ducts could improve the pressure distribution around the radiator bundle, reinforce the lateral air intake, and reduce the intensity of mainstream vortices, so as to enhance the ventilation rate of a NDDCT. For an outstanding performance, the two-duct wind collecting scheme is suggested, which may assure a NDDCT working in an approximately wind free manner in all investigated cross-wind range, and increase the ventilation rate by ~63% under the high cross-wind condition, which may reduce the overall coal consumption by 23500~33500 tons annually for a 660 MW coal-fired unit. The numerical results are confirmed by a hot state modelling experiment conducted in a wind tunnel.
KEYWORDS
cross-wind, flow loss factor, NDDCT, lateral flow acceleration, ventilation enhancement, wind collecting
PAPER SUBMITTED: 2018-10-31
PAPER REVISED: 2018-10-28
PAPER ACCEPTED: 2019-01-24
PUBLISHED ONLINE: 2019-09-22
DOI REFERENCE: https://doi.org/10.2298/TSCI19S4013W
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2019, VOLUME 23, ISSUE Supplement 4, PAGES [S1013 - S1024]
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Utilization of the lateral accelerated cross-wind to improve the cooling performance of a natural draft dry cooling tower

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