Urban growth has promoted the use of underground spaces,where explosion accidents can be catastrophic.In this study,we investigated the effect of placing flexible construction in front of rigid obstacles on methane ex...Urban growth has promoted the use of underground spaces,where explosion accidents can be catastrophic.In this study,we investigated the effect of placing flexible construction in front of rigid obstacles on methane explosion protection by using an experimental platform and adjusting the blockage rate and spacing of the obstacles.It aims to reduce the risk of gas explosions in urban underground spaces.The results of the study show that the flame propagation peak speed and peak overpressure are reduced with the decrease in the blocking rate of the flexible obstacle when the blocking rate of the flexible obstacle is less than or equal to the blocking rate of the rigid obstacle,with the decrease in the spacing,the better the protection effect of the methane explosion.When the blockage rate of the flexible obstacle is greater than the blockage rate of the rigid obstacle and spacing is less than the height of the flexible obstacle,rigid and flexible obstacles are connected as a whole,increasing the strength of the explosion.This study can provide a theoretical basis and scientific guidance for optimizing rigid and flexible object hybrid layouts and methane explosion protection technology in urban underground spaces.展开更多
评述了4种炸药感度判据,包括最易跃迁法(最小能隙)、最小键级、最弱键离解能、X—NO2(XC,N or O)中硝基的Mulliken电荷。首次提出了基于炸药分子整体稳定性的名为"键&非键耦合分子刚柔度"的新的感度判据。比较了11种典...评述了4种炸药感度判据,包括最易跃迁法(最小能隙)、最小键级、最弱键离解能、X—NO2(XC,N or O)中硝基的Mulliken电荷。首次提出了基于炸药分子整体稳定性的名为"键&非键耦合分子刚柔度"的新的感度判据。比较了11种典型炸药[1,3,5-三硝基苯(TNB)、2,4,6-三硝基甲苯(TNT)、1,3,3-三硝基氮杂环丁烷(TNAZ)、1,3,5-三硝基-1,3,5-三氮杂环己烷(RDX)、1,3,5-三硝基-2-氧-1,3,5-三氮杂环己烷(K6)、2,4,6,8,10,12-六硝基-2,4,6,8,10,12-六氮杂异伍兹烷(CL-20)、2-苦基-1,2,3-三唑(P CTA)、4-硝基-2-苦基-1,2,3-三唑(NPCTA)、2,6-二氨基-3,5-二硝基吡啶-1-氧化物(LLM-105)、4,6-二硝基苯并氧化呋咱(DNBF)、5,7-二氨基-4,6-二硝基苯并氧化呋咱(DADNBF)]的撞击感度与判据之间的相关性。结果表明,在这5种感度判据中,"键!非键耦合分子刚柔度"评价方法的相关性最高。判据组合能提高预测感度的能力。张力能是炸药分子中键!非键耦合能的一种形式,它不仅能够用于衡量炸药的感度,尤其是不含硝基炸药的感度,同时还能用来量度炸药的储能水平,这对新型炸药的设计和评价具有重要意义。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52274177)Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJZD-K202401501)+1 种基金Chongqing Graduate Student Research Innovation Program(Grant No.CYS240800)The Science and Technology Innovation Project for Graduate Students of Chongqing University of Science and Technology(Grant No.YKJCX2420702).
文摘Urban growth has promoted the use of underground spaces,where explosion accidents can be catastrophic.In this study,we investigated the effect of placing flexible construction in front of rigid obstacles on methane explosion protection by using an experimental platform and adjusting the blockage rate and spacing of the obstacles.It aims to reduce the risk of gas explosions in urban underground spaces.The results of the study show that the flame propagation peak speed and peak overpressure are reduced with the decrease in the blocking rate of the flexible obstacle when the blocking rate of the flexible obstacle is less than or equal to the blocking rate of the rigid obstacle,with the decrease in the spacing,the better the protection effect of the methane explosion.When the blockage rate of the flexible obstacle is greater than the blockage rate of the rigid obstacle and spacing is less than the height of the flexible obstacle,rigid and flexible obstacles are connected as a whole,increasing the strength of the explosion.This study can provide a theoretical basis and scientific guidance for optimizing rigid and flexible object hybrid layouts and methane explosion protection technology in urban underground spaces.
文摘评述了4种炸药感度判据,包括最易跃迁法(最小能隙)、最小键级、最弱键离解能、X—NO2(XC,N or O)中硝基的Mulliken电荷。首次提出了基于炸药分子整体稳定性的名为"键&非键耦合分子刚柔度"的新的感度判据。比较了11种典型炸药[1,3,5-三硝基苯(TNB)、2,4,6-三硝基甲苯(TNT)、1,3,3-三硝基氮杂环丁烷(TNAZ)、1,3,5-三硝基-1,3,5-三氮杂环己烷(RDX)、1,3,5-三硝基-2-氧-1,3,5-三氮杂环己烷(K6)、2,4,6,8,10,12-六硝基-2,4,6,8,10,12-六氮杂异伍兹烷(CL-20)、2-苦基-1,2,3-三唑(P CTA)、4-硝基-2-苦基-1,2,3-三唑(NPCTA)、2,6-二氨基-3,5-二硝基吡啶-1-氧化物(LLM-105)、4,6-二硝基苯并氧化呋咱(DNBF)、5,7-二氨基-4,6-二硝基苯并氧化呋咱(DADNBF)]的撞击感度与判据之间的相关性。结果表明,在这5种感度判据中,"键!非键耦合分子刚柔度"评价方法的相关性最高。判据组合能提高预测感度的能力。张力能是炸药分子中键!非键耦合能的一种形式,它不仅能够用于衡量炸药的感度,尤其是不含硝基炸药的感度,同时还能用来量度炸药的储能水平,这对新型炸药的设计和评价具有重要意义。