半封闭空间内氢化镁粉尘爆炸火焰的传播特性  

Characteristics of hydrogenated magnesium dust explosion flame propagating in a semi-enclosed space

作　　者：毛文哲 张国涛 杨帅帅 徐子晖 王燕[1,2,3] 纪文涛[1,2,3] MAO Wenzhe;ZHANG Guotao;YANG Shuaishuai;XU Zihui;WANG Yan;JI Wentao(College of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo 454003,Henan,China;Explosion Dynamic Disaster Early Warning and Emergency Engineering Technology Research Center of Henan Province,Henan Polytechnic University,Jiaozuo 454003,Henan,China;Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization,Henan Polytechnic University,Jiaozuo 454003,Henan,China)

机构地区：[1]河南理工大学安全科学与工程学院,河南焦作454003 [2]河南理工大学河南省燃爆动力灾害预警与应急工程技术研究中心,河南焦作454003 [3]河南理工大学煤炭安全生产与清洁利用省部共建协同创新中心,河南焦作454003

出　　处：《爆炸与冲击》2024年第6期172-182,共11页Explosion and Shock Waves

基　　金：国家自然科学基金(52374197,U22A20120);河南省优秀青年科学基金(212300410042)。

摘　　要：在自行搭建的5 L粉尘爆炸火焰传播特性实验装置中,实验研究了半封闭空间内氢化镁(MgH_(2))粉尘爆炸火焰的传播特性。实验结果表明:随MgH_(2)粉尘浓度的提高,MgH_(2)粉尘爆炸火焰由点火至稳定传播所用时间先缩短后延长以及预热区宽度先减小后增大,火焰亮度、锋面平滑度、及火焰传播速度呈先提高后降低的趋势,并在质量浓度为800 g/m^(3)时呈最佳燃烧状态。不同浓度的MgH_(2)粉尘爆炸火焰传播瞬时速度整体呈波动趋势,波动幅度随浓度的提高而先减小后增大,800 g/m^(3)时波动幅度最小,瞬时传播速度变化趋势随浓度的变化呈现不同的变化趋势。最后,根据MgH_(2)爆炸产物的XRD测试结果,分析MgH_(2)粉尘爆炸反应机理,发现MgH_(2)粉尘爆炸是以MgH_(2)燃烧反应为主并伴随有MgH_(2)和Mg(OH)2分解以及Mg和H_(2)氧化等多个总包反应的复杂过程,爆炸反应的最终产物为MgO。In the experiment conducted using a custom-built 5-L dust explosion flame propagation apparatus,the focus of the study was the characteristics of the flame propagation of magnesium hydride(MgH_(2))dust explosions within a semi-enclosed space.The experimental results showed that as the concentration of MgH_(2)dust increased,the time required for the MgH_(2)dust explosion flame to transfer from ignition to stable propagation decreased initially,but then increased as the dust concentration further increased.Similarly,the width of the preheating zone followed the same pattern.Initially,it decreased with increasing dust concentration,but once the concentration reached a certain threshold,it started to increase.Beyond that,the flame brightness,smoothness of the flame front,and flame propagation speed all showed similar trends.They initially increased as the MgH_(2)dust concentration increased,suggesting enhanced combustion activity.However,as the concentration further increased,these characteristics started to decline,indicating a diminishing combustion efficiency.The best combustion state was observed at a dust mass concentration of 800 g/m^(3).The instantaneous speed of the MgH_(2)dust explosion flame propagation exhibited a fluctuating pattern across different concentrations.The fluctuation amplitude initially decreased as the dust concentration increased,suggesting a more stable flame propagation.However,beyond a certain concentration,the fluctuation amplitude began to increase again.It is worth noting that the change in instantaneous propagation speed variation displayed different trends as the concentration varied.The exact behaviors were found to be dependent on the particular concentration level.Finally,analysis of the X-ray diffraction(XRD)test results of the MgH_(2)explosion products revealed a complex reaction mechanism.The MgH_(2)dust explosion primarily involved the combustion reaction of MgH_(2)but also included multiple overall reactions such as the decomposition of MgH_(2)and Mg(OH)2,as well as the oxid

关 键 词：半封闭空间 储氢金属 氢化镁 爆炸 火焰传播 

分 类 号：O381[理学—流体力学]