NUMERICAL INVESTIGATION OF THE PERFORMANCE VARIATION OF A FAN-HEAT EXCHANGER SYSTEM FOR POWER TRANSFORMERS UNDER EXTERNAL WIND CONDITIONS

B.G. Cha; S. Park; K. Park; J.K. Min

doi:10.6112/kscfe.2026.31.3.131

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2026 Vol.31, Issue 3 Preview Page Next Page

Original Article

NUMERICAL INVESTIGATION OF THE PERFORMANCE VARIATION OF A FAN-HEAT EXCHANGER SYSTEM FOR POWER TRANSFORMERS UNDER EXTERNAL WIND CONDITIONS 외부 풍속 조건에 따른 발전소용 주변압기 팬-열교환기 시스템의 성능변화에 관한 수치적 연구

30 September 2026. pp. 131-144

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Abstract

This study applied a simplified system-level CFD model to evaluate the cooling performance of an outdoor air-cooled fan–heat exchanger system for a power-plant transformer under various external wind conditions. The fan was modeled using the pressure-jump method, while the heat exchanger core was simplified using an air/oil-coupled dual-cell porous media model combined with an ε-NTU heat transfer model. This approach enables the flow rate and heat transfer performance of the system to be evaluated under various external wind conditions without directly resolving the detailed fin-tube geometry or fan blades. The external wind conditions were determined based on meteorological data from the power-plant installation region, with wind speeds ranging from 0 to 20 m/s and wind directions of γ = 0°, 45°, and 90°. The results showed that the frontal wind condition, γ = 0°, caused the most significant performance degradation, with the heat transfer rate and fan flow rate decreasing by up to approximately 52% and 50%, respectively, compared with the calm (no wind) condition. Meanwhile, under the crosswind condition of γ = 90°, the heat transfer performance decreased even though the fan flow rate increased. This indicates that wind-induced distortion of the fan outlet flow can reduce the effective cooling performance of the system. Therefore, the proposed simplified CFD can be applied to evaluating system-level cooling performance variations caused by fan operating-point shifts and fan outlet flow distortion under external wind conditions.

Keywords

공랭식 열교환기 (Air cooled heat exchanger)

외풍 조건(External wind condition)

수치 해석(Numerical analysis)

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Information

Publisher :Korean Society for Computational Fluids Engineering
Publisher(Ko) :한국전산유체공학회
Journal Title :Journal of Computational Fluids Engineering
Journal Title(Ko) :한국전산유체공학회지
Volume : 31
No :3
Pages :131-144
Received Date : 2026-07-23
Revised Date : 2026-09-04
Accepted Date : 2026-09-11
DOI :https://doi.org/10.6112/kscfe.2026.31.3.131

Journal of Computational Fluids Engineering ISSN:1598-6071(Print) 3022-6252(Online) 한국전산유체공학회지

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