THERMAL SCIENCE

International Scientific Journal

Yingguang Li

,

Zeru Zhou

,

Biren Lin

,

Hao Zhang

,

Weifeng Huo

,

Honglei Deng

,

Gang Liu

ANALYSIS OF EXTERNAL HEAT DISSIPATION ENHANCEMENT OF OIL-IMMERSED TRANSFORMER BASED ON FALLING FILM MEASURE

ABSTRACT
With the increase of power load, the overheating problem of oil-immersed transformer in operation cannot be ignored. Therefore, it is necessary to propose reasonable heat dissipation enhancement measure for oil-immersed transformer in operation and study the influence of the measure on the internal temperature of transformer. The heat transfer process of oil-immersed transformer is analyzed, and the air-side heat transfer coefficient is pointed out to be the important parameter limiting the heat dissipation capacity of the transformer. In order to improve heat dissipation capacity, the measures based on cooling fans and falling film are proposed and the calculation methods for the air-side heat transfer coefficient are conducted, respectively. Moreover, the top-oil temperature and hot-spot temperature under two measures are compared by the thermal-fluid coupling model of oil-immersed transformer. For the transformer operating at rated load and the ambient temperature of 25°C, after the cooling fans are adopted, the top-oil temperature and hot-spot temperature can be reduced by 22.4°C and 20.7°C, while after the falling film is adopted, the top-oil temperature and hot-spot temperature can be reduced by 31.2°C and 28.7°C, respectively. The results show that the falling film is a more effective heat dissipation enhancement measure, which can meet the higher load demand of oil-immersed transformer.
KEYWORDS
oil-immersed transformer, the air-side heat transfer coefficients, heat dissipation enhancement measure, cooling fans, Falling film
PAPER SUBMITTED: 2021-04-09
PAPER REVISED: 2021-11-25
PAPER ACCEPTED: 2021-12-03
PUBLISHED ONLINE: 2022-04-09
DOI REFERENCE: https://doi.org/10.2298/TSCI211015041L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2022, VOLUME 26, ISSUE Issue 6, PAGES [4519 - 4533]
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Analysis of external heat dissipation enhancement of oil-immersed transformer based on falling film measure

© 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