煤矿许用炸药爆燃倾向测试方法

在分析现有爆燃测试方法的基础上，建立了一种薄壁式的爆燃倾向测试装置，并按新颁布为行为标准对几种粉状炸药进行了测试，还试用压力测试来评价炸药的爆燃倾向。     

含能材料多孔颗粒床中致密波分析

本文采用一维两相流模型模拟了活塞驱动多孔颗粒床这一动态过程。用线方法 ( MOL)对该方程组求数值解。计算表明 ,经过短暂的非稳态过程 ,颗粒床中形成一稳态致密波 ,分析了致密波的结构以及活塞速度边界条件对致密波结构的影响规律。     

PBX-2炸药加热条件下燃烧转爆轰特性

为了研究炸药在加热前后的燃烧转爆轰特性变化,设计了加热条件下燃烧转爆轰试验加载系统,对Φ30 mm ×400 mm的PBX-2炸药进行了试验。试验中采用热电偶测试装置壳体和炸药表面温度变化过程,采用离子探针测量了燃烧转爆轰过程的传播时间和距离,探讨了加热与未加热PBX-2炸药的燃烧转爆轰特性。结果表明,与未加热相比,加热至85℃时PBX-2炸药更难以发生燃烧转爆轰现象。     

Fe2O3-Al纳米铝热剂与超细RDX复合物的制备与性能

采用溶胶-凝胶方法,制备出了纳米铝热剂nano-Fe2O3-Al,并获得了其与超细RDX的复合含能材料nanoFe2O3-Al/SFRDX。采用BET法、SEM、XRD综合表征了nano-Fe2O3-Al的结构,采用TG/DSC联用技术测试了nano-Fe2O3-Al的热性能,结果表明气凝胶铝热剂的反应温度更低;nano-Fe2O3-Al的静电火花感度测试结果表明纳米铝热剂对静电十分敏感。对nano-Fe2O3-Al/SFRDX在无约束条件和密闭条件下的燃烧行为进行了研究,高速相机照片法发现在无约束条件下,nanoFe2O3-Al燃烧高达300 m/s,且nano-Fe2O3-Al/SFRDX具有在无约束条件下由燃烧转为爆轰的趋势。     

含90°直角弯管结构受限空间油气泄压爆炸实验与大涡模拟研究

针对含90°直角弯管结构受限空间油气泄压爆炸特性进行了研究,采用高速摄影等技术对爆炸过程中的压力瞬变、火焰形态进行了采集,同时对实验进行了大涡模拟,精确模拟了火焰经过弯管时的超压特性、流场结构以及火焰形态,并与实验结果进行了对比分析。结果表明：（1）弯管结构对于爆炸过程中火焰结构有影响,在受限空间内火焰形态发生“半球形-指尖形-毛刷状”三种形态转变。（2）在弯管处形成的毛刷状火焰是由弯管局部压力梯度形成的涡流导致的。（3）衍射波与反射波在弯管处的叠加对爆炸超压峰值具有强化作用。（4）爆炸过程中,爆炸超压峰值、火焰速度、火焰锋面面积表现出显著的耦合性,具有密切的内在联系,三者随时间变化趋势存在较强的一致性。     

小尺度受限空间内瓦斯爆燃的动态特性

为获得包括瓦斯爆燃点火初期、火焰加速、减速及二次加速过程中动态火焰微细结构及其与超压之间的相互关系,实验研究了小尺度受限空间内瓦斯爆燃火焰形状、火焰锋面位置、火焰速度及超压等动态特性.研究结果表明,在无障碍物条件下,火焰锋面光滑,火焰形状由"半球"状逐渐演变为"手指"状;而有障碍物条件下,火焰锋面出现明显褶皱和湍流现象,其火焰速度经历两次加速和一次减速过程,最大火焰速度达112m/s,与无障碍物条件下最大值相比增幅为124%;当火焰锋面经过障碍物后即将重新汇合时,出现8.5kPa的最大超压,与无障碍物条件下的最大值相比增幅为118%.     

Formation of carbon clusters in deflagration and detonation waves in gas mixtures

Numerical and experimental results of studying the formation of carbon clusters due to propagation of deflagration and detonation waves in enriched acetylene-oxygen and acetylene-air mixtures are described. Experiments are performed in tubes of different diameters (including tubes filled by a porous medium) with wide-range variations of the initial pressure and the fuel-to-oxidizer ratio. A large variety of carbon clusters formed in different regimes of burning of the mixture is found. A typical size of condensed carbon particles is 15–100 nm. In the case of detonation in a porous medium, the size of carbon particles is 15–45 nm; in some tests, large individual fullerene-type particles 150, 400, and 950 nm in size are formed. The fraction of condensed carbon in the total amount of carbon in the initial mixture is found to depend on the wave type; detonation is characterized by the minimum “yield” of condensed carbon. The amount of condensed carbon increases with increasing acetylene concentration in the mixture and initial pressure. The size of carbon particles in the case of deflagration is greater than that in the case of detonation. Cooling of reaction products decelerates condensation and interrupts the growth of carbon particles. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 3, pp. 81–94, May–June, 2008.     

正压直吹式制粉系统爆燃分析及对策

直吹式制粉系统燃用高挥发分烟煤时,易发生爆燃事故,通过一次磨煤机爆燃事故的分析,找出爆燃原因,并采取相应措施,为类似情况提供借鉴。     

Fast turbulent deflagration and DDT of hydrogen–air mixtures in small obstructed channel

An experimental study of flame propagation, acceleration and transition to detonation in hydrogen–air mixture in 2-m long rectangular cross-section channel filled with obstacles located at the bottom wall was performed. The initial conditions of the hydrogen–air mixture were 0.1 MPa and 293 K. Three different cases of obstacle height (blockage ratio 0.25, 0.5 and 0.75) and four cases of obstacle density were studied with the channel height equal to 0.08 m. The channel width was 0.11 m in all experiments. The propagation of flame and pressure waves was monitored by four pressure transducers and four in-house ion probes. The pairs of transducers and probes were placed at various locations along the channel in order to get information about the progress of the phenomena along the channel. To examine the influence of mixture composition on flame propagation and DDT, the experiments were performed for the compositions of 20%, 25% and 29.6% of H₂ in air by volume. As a result of the experiments the deflagration and detonation regimes and velocities of flame propagation in the obstructed channel were determined.     

管内低浓度抽采瓦斯爆燃控制方法研究

水雾、CO2惰性气体和干粉对瓦斯爆燃有很强的抑制作用。随着喷雾量的增大,混入CO2浓度或者喷入干粉质量的增大,火焰传播速度和峰值超压都减少。水雾,惰性气体CO2以及干粉对爆燃的抑制作用在于由于水雾、惰性气体CO2以及干粉的加入,降低了链式反应中H、O和OH等高活性自由基的浓度。