Study on influence factors of formation and development of jet fire in confined space

doi:10.16265/j.cnki.issn1003-3033.2020.07.006

Abstract

Abstract: In order to prevent and control transformer oil fire and ensure normal operation of power grid, influence of transformer oil volume, core and winding volume on formation and development of jet fire was studied. Firstly, a small transformer oil combustion test platform was built, and fire forms in confined space were analyzed at generation, development and extinction stages. Secondly, changes of fire forms in each stage were analyzed after changing quantity of transformer oil. Finally, same analysis was carried out for changes of ball filling quantity. The results show that BLEVE is a key point for the biggest jet height. As quantity of transformer oil reduces, overall energy in the tank is lowered, causing a drop of flame height and delay of fire appearance at each stage. After adding 2.4 dm³ steel balls to tank, thermal resistance at bottom increases. Moreover, their protrusions or depressions provide a gasification core for bubbles in boiling process, thus decreasing liquid superheat and enhancing heat transfer. As a result, flame height is lowered significantly and time of jet fire is delayed by 52.91%

Key words: confined space, jet fire, transformer oil, boiled liquid evaporate vapor explosion (BLEVE), filling quantity

CLC Number:

X934

CHEN Qing, WEI Xu, CHEN Guang, XU Liang, CHEN Peng, LIU Yang. Study on influence factors of formation and development of jet fire in confined space[J]. China Safety Science Journal, 2020, 30(7): 35-40.

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