摘要
为防控换流变火灾的发生,确保电网的正常运行,研究换流变内变压器油的量、铁芯及绕组等所占体积对射流火形成和发展的影响。首先,搭建小型变压器油燃烧试验平台,分析受限空间射流火产生、发展、熄灭等阶段火焰形式;然后,改变变压器油的量,分析各阶段射流火形态的变化;最后,改变钢珠填充量,分析射流火形态。研究结果表明:沸腾液体蒸发蒸气爆炸(BLEVE)现象是喷射高度达到最高的关键点;减少罐内变压器油的充装量后罐内整体能量降低,这导致各阶段火焰高度降低,且各阶段火焰显现时刻出现延后;加入2.4 dm3钢珠后,罐底热阻增大,而钢珠表面的突起或凹陷为沸腾过程的气泡提供气化核心,降低液相过热度,强化传热效果,使火焰高度大幅降低的同时,将射流火出现时刻延迟52.91%。
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%.
作者
陈庆
魏旭
陈光
徐亮
陈鹏
刘洋
CHEN Qing;WEI Xu;CHEN Guang;XU Liang;CHEN Peng;LIU Yang(State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing Jiangsu 210024,China;State Grid Electric Power Research Institute Co.,Ltd.,Nanjing Jiangsu 211106,China;School of Emergency Management&Safety Engineering,China University of Mining&Technology Beijing,Beijing 100086,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2020年第7期35-40,共6页
China Safety Science Journal
基金
国家电网公司科技项目(8000-201918445A-0-0-00)。
