摘要
密闭容器内预混气体爆炸非常复杂,为研究点火位置对甲烷/空气预混气体爆炸特性的影响,在初始压力为101 kPa和初始温度为300 K的环境下,开展1 m^(3)密闭球形爆炸容器中10 vol%甲烷浓度的中心点火爆炸实验,并使用Fluent数值模拟软件,采用LES湍流模型和Zimont燃烧模型,研究不同点火位置(中心点火、0.5R点火、R点火)对容器内甲烷/空气预混气体爆炸特性的影响,包括火焰结构演化、爆炸温度、爆炸压力、爆炸压力上升速率。结果表明:(1)在中心、0.5R和R处点火时,火焰分别向四周膨胀直至容器壁面、轮廓由最初的“左薄右厚”逐渐转变为“左侧凸起的尖角”和在壁面处从“圆弧形”逐渐拉伸转变成“尖形”向左侧发展;(2)不同点火位置下温度场存在温度梯度,升温规律均由点火中心能量持续向外释放,温度不断积聚升高;(3)不同点火位置下爆炸压力变化趋势基本一致,由于壁面绝热,最终最大爆炸压力均稳定在766 kPa左右;(4)中心点火时最大爆炸压力上升速率最大,较0.5R点火和R处点火分别增大了94.5%和141.8%。
The explosion of premixed gas in a closed vessel is very complicated.In order to study the effect of ig-nition position on the explosion characteristics of methane/air premixed gas,the central ignition explosion experiment with 10 vol.%methane concentration in a 1 m^(3) closed spherical explosive vessel was carried out under an initial pressure of 101 kPa and an initial temperature of 300 K.Besides,the ffect of different ignition positions(center ignition,0.5R ignition,R ignition)on the explosion characteristics of methane/air premix in the vessel was studied by LES turbulence model and Zimont combustion model of the Fluent numerical simulation software.It includes flame structure evolution,explosion temperature,explosion pressure and explosion pressure rise rate.The results show that the flame expands around until the wall and profile of the vessel gradually change from the initial"left thin and right thick"to the"left raised sharp angle"and gradually stretch from the"circular arc"to the"sharp shape"to the left when the flame is ignited at the center,0.5R and R.And then,there is a temperature gradient in the temperature field at different ignition positions.The heating law is continuously released from the energy of the ignition center,and the temperature continuously accumulates and rises.Furthermore,the variation trend of explosion pressure under different ignition positions is basically the same.The final maximum explosion pressure is stable at about 766 kPa due to the wall insulation.Finally,the rise rate of the maximum explosion pressure in the center ignition is the highest,which is 94.5%and 141.8%higher than that in 0.5R ignition and R ignition,respectively.
作者
王金贵
梁志星
胡强强
朱杭钦
胡超
魏林慧
WANG Jin-gui;LIANG Zhi-xing;HU Qiang-qiang;ZHU Hang-qin;HU Chao;WEI Lin-hui(College of Environment and Safety Engineering,Fuzhou University,Fuzhou 350116,China)
出处
《爆破》
CSCD
北大核心
2024年第1期186-195,共10页
Blasting
基金
福建省自然科学基金资助项目(2020J01505)。
关键词
点火位置
甲烷/空气预混气体
火焰前锋
大涡模拟
密闭球形容器
ignition position
methane/air premixed gas
flame front
large eddy simulation
hermetically sealed spherical vessel
作者简介
王金贵(1987-),男,博士、副教授,(E-mail)wjgfzu@126.com;通讯作者:魏林慧(1998-),女,硕士研究生,(E-mail)2462928706@qq.com。
