THERMAL SCIENCE

International Scientific Journal

Xingrong Zhu

,

Tingfang Yu

,

Jianyong Zhan

,

Ying Zhou

INVESTIGATION OF THE PERFORMANCE OF COLD-END SYSTEM IN DIRECT AIR-COOLED POWER UNITS UNDER THE INFLUENCE OF AMBIENT WINDS

ABSTRACT
Direct air-cooled condensers in power plants rely on heat transfer with the atmospheric environment to discharge thermal energy. The heat transfer process becomes complicated in practical operations when ambient wind is involved. To examine the impact of wind on the heat transfer performance of direct air-cooled condensers, this paper took into consideration three different wind directions, namely, headwind, crosswind and tailwind, as well as four different speeds (3 m/s, 6 m/s, 9 m/s, and 12 m/s), and numerically investigated their influences on the thermal performance of a 600 MW direct air-cooled power unit. The variation in ventilation rates and inlet air temperatures among the cells under the influence of ambient winds are also studied. Simulation results indicated that ambient winds induced thermal air re-circulation and air backflow phenomena in the air-cooled island. The cells located on the windward side were significantly affected in all three wind direction conditions. The ventilation rates and inlet air temperatures among the cells were not uniform, showing an overall increasing trend. In particular, negative pressure zones were generated under tailwind conditions, severely impacting air-flow rates at the fan inlet, and inlet air temperatures of cells. These phenomena became more pronounced with increasing wind speeds.
KEYWORDS
Direct air-cooled condenser, numerical simulation, ambient wind, heat transfer performance
PAPER SUBMITTED: 2023-06-09
PAPER REVISED: 2023-09-20
PAPER ACCEPTED: 2023-11-30
PUBLISHED ONLINE: 2024-03-10
DOI REFERENCE: https://doi.org/10.2298/TSCI230609046Z
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE Issue 3, PAGES [2433 - 2446]
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Investigation of the performance of cold-end system in direct air-cooled power units under the influence of ambient winds

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence