爆炸波膨化法对木质纤维材料形态结构的影响

采用爆炸波膨化法对速生杨木片进行处理,用扫描电镜观测分析爆炸波膨化处理前后杨木片的组织形态变化。实验结果表明:未经爆炸波处理的原始状态的杨木(片)材料,其纤维组织的扫描显微图像呈致密的导管状分布,而且导管间纵向平行排列;经爆炸波处理后,杨木材料的扫描显微图像呈现无序排列的纤维形态,纤维组织的致密度大大降低,这将有利于增强液体对木质纤维组织的浸渍、润胀等作用。     

爆炸冲击波在码头建筑物中的传播与爆炸当量的计算

本文以流动力学和爆炸力学为基础,利用了已有的城市建筑爆炸模型数据,通过对实际现场以及一般码头的建筑分布研究,提出了一个适用于码头的爆炸冲击模型,并利用LSDYNA3D软件,采用ALE方法,针对城市多元化的复杂环境,研究爆炸波的传播规律及其对主建筑物产生的超压荷载,做出爆炸超压-比例距离曲线分布图。结合超压对建筑物的损坏情况表,可计算出爆炸中心的当量TNT,从而估算出爆炸现场的整体受损情况。     

爆炸冲击波绕过墙体的数值模拟研究

利用ALE算法和炸药爆轰产物的JWL状态方程对爆炸冲击波绕过墙体的环流现象进行了数值模拟,得到了在爆炸物周围有障碍物的爆炸场初始发展和绕过墙体环流的情况,解析了空气冲击波的绕流规律。实验结果与数值模拟基本相符,反映了爆炸波绕过障碍物的详细过程。     

空气及半硬质聚氨酯泡沫塑料中爆炸波传播特性的研究

对半硬质聚氨脂泡沫(SRPUF)塑料中雷管爆炸场的反射压力分布进行了测试,并利用理想气体状态方程将空气中雷管爆炸后所测的入射压力分布转化成反射压力分布.对这两种介质(空气、SRPUF材料)中反射压力分布进行了对比和分析,定性地讨论了两种介质中爆炸波的传播特性,并对SRPUF材料隔爆缓冲性能进行了分析说明.     

海上油气田相邻生产装置间的安全距离研究

本文采用挪威船级社(DNV)的PHAST软件进行井喷事故后果模拟分析,首次通过计算分析扩散距离、火焰热辐射距离、爆炸波影响等,确定出海上油气田相邻生产装置间可接受的最小安全距离。     

LPG蒸气云爆炸风险评估中的参数不确定性分析

分析了液化石油气的危险特性及其事故性爆炸的主要特点,针对蒸气云爆炸定量风险评估中不确定因素无法精确确定而导致的结果不确定性问题,即蒸气云爆炸事故造成的危害存在不确定性,建立了蒸气云爆炸风险评估模型,提出了一种基于Monte Carlo模拟的不确定性处理方法,计算了LPG蒸气云爆炸波伤害范围和事故风险概率曲线,对于定量评估VCE事故风险具有重要意义。     

AUTO-DYN模拟炸药爆炸问题的分析

通过CAD/CAE软件建立了不同装药质量与网格尺寸的半无限爆炸场模型,利用AUTO-DYN有限元程序计算出爆炸波的超压值和正压作用时间.将模拟结果与实验数据进行了比较.结果表明,AUTO-DYN有限元程序在模拟爆炸场时,近、中场的计算结果与实验误差相对较大,而远场的计算结果与实验的误差相对较小.计算模型的网格尺寸、计算区域大小和计算机的计算能力对模拟结果有影响.直接使用AUTO-DYN模拟爆炸场对人体的创伤效应存在一定局限性.     

游离氨对污水生物脱氮的影响综述

总结了游离氨(FA)抑制生物脱氮过程(BNR)的最新研究。主要介绍了FA对氨氧化菌(AOB)和亚硝酸盐氧化菌(NOB)的抑制阈值、抑制机理和抑制模型以及FA对反硝化菌的抑制作用。同时探讨了如何利用FA选择性抑制来实现短程硝化反应,并且展望了FA对BNR影响的研究方向。     

游离氨对污水生物脱氮的影响综述

总结了游离氨(FA)抑制生物脱氮过程(BNR)的最新研究。主要介绍了FA对氨氧化菌(AOB)和亚硝酸盐氧化菌(NOB)的抑制阈值、抑制机理和抑制模型以及FA对反硝化菌的抑制作用。同时探讨了如何利用FA选择性抑制来实现短程硝化反应,并且展望了FA对BNR影响的研究方向。     

水分蒸发抑制剂的实验研究

本研究是利用人们对表面活性剂分子结构研究的成果 ,并以单分子表面膜理论为基础 ,对高级脂肪醇抑制水分蒸发效果做了较细致的研究。讨论了乳液粒度、醇链长度、混合表面活性剂以及温度对抑制效果的影响     

应用二维黏性CE/SE方法模拟挡波墙对爆炸流场的影响

应用高精度的二维黏性CE/SE方法模拟爆点周围有挡波墙的爆炸流场,分析了挡波墙与冲击波相互作用的规律,得到了能够反映波系结构变化的压力等值线图.数值计算结果显示了冲击波遇挡波墙发生反射、绕流等现象;通过与无挡波墙时的爆炸流场对比,分析了挡波墙的削波作用;同时考察了挡波墙的高度、厚度对远场压力的影响.数值计算结果对于爆炸流场的防护具有理论指导意义.     

Secondary sites of fire in an explosion of organic dust

Formulas for the pressure, momentum, and time of impact of a shock as functions of the energy of a spherical explosion in air and the distance to the center of the explosion are used to calculate parameters of the incident and reflected (from a rigid obstacle) shock waves produced by an explosion of a concentrated mass of organic dust. The distances from the explosion center are determined within which the temperature in the incident or reflected shock waves exceeds the ignition temperature of the particles suspended in air and secondary sites of fire can be initiated by the shock passing through the dusty space. Translated fromFizika Goreniya i Vzryva, Vol. 36, No. 3, pp. 60–64, May–June, 2000.     

Seismic, Hydroacoustic, and Acoustic Action of Underwater Explosions

Results of a fullscale study of hydroacoustic, seismic, and acoustic effects of an underwater explosion of charges of a chemical high explosive are described. The study had a comprehensive character and included video filming of surface phenomena at the explosion epicenter, registration of hydroacoustic waves in water, seismic waves on the ground, and acoustic waves in air at distances of 0.08–30 km from the explosion epicenter. Parameters of these waves and the character of their decay with distance were obtained, and the wave spectra were analyzed. It is shown that the main specific feature of the wave shapes of hydroacoustic, seismic, and acoustic signals is caused by oscillations of the cavity filled by detonation products, which can be used to identify underwater explosions.     

含草酸钾的超细水雾抑制甲烷爆炸的特性

为研究含草酸钾的超细水雾对抑制甲烷爆炸有效性的影响,采用自制的半封闭管道进行抑爆实验,研究了草酸钾浓度的变化对超细水雾粒径的影响以及对甲烷抑爆性能的影响,分析了不同浓度草酸钾条件下火焰传播速度、爆炸超压、平均升压速率以及爆炸威力指数参数变化。实验结果表明：添加草酸钾对超细水雾的粒径特性影响较小;对于体积分数为9.5%的甲烷,在相同的通雾时间下,当草酸钾浓度为2%时,抑爆性能最显著,火焰传播速度、最大爆炸超压、平均升压速率以及爆炸威力指数较纯甲烷自由爆炸时分别下降了57.1%、66.3%、77.9%、91.5%;较纯水超细水雾分别下降了43.1%、61.3%、75.3%、90.5%;草酸钾的热解温度较低能够增强超细水雾的物理惰化作用并阻断化学链式反应从而有效抑制甲烷爆炸。     

含NaCl荷电细水雾对甲烷爆炸火焰传播的抑制特性

为进一步提高细水雾抑制甲烷爆炸的效率,搭建了小尺寸细水雾抑制甲烷爆炸实验平台,在普通细水雾中添加NaCl添加剂,并对其荷电,进行含NaCl添加剂荷电细水雾抑制甲烷爆炸火焰传播特性的实验研究。结果表明,含NaCl添加剂荷电细水雾对甲烷爆炸火焰传播的抑制效果,优于普通细水雾单独添加NaCl添加剂和荷电作用的抑制效果之和。随着NaCl浓度和荷电电压的增大,甲烷爆炸火焰传播速度明显减小;其中荷电8 kV、NaCl浓度12.5%的工况抑制效果最佳,甲烷爆炸火焰传播速度二次峰值较普通细水雾作用时下降了10.747 m·s^-1,下降比例高达60.26%;分析认为,在细水雾抑制甲烷爆炸火焰传播的过程中,NaCl添加剂和荷电作用之间存在相互促进抑制效果的耦合作用。     

Coal dust/air explosions in a large-scale tube

Coal dust/air mixture explosions under weak ignition conditions have been studied in a horizontal experimental tube of diameter 199 mm and length 29.6 m. The experimental tube is closed at one end and open at the downstream end. An array of 40 equally spaced dust dispersion units was used to disperse coal dust particles into the experimental tube. The coal dust/air mixture was ignited by an electric spark. A constant-temperature hot-wire anemometer was used to measure the gas velocity during the dispersion process. Kistler piezoelectric pressure sensors were used to measure the propagation of the pressure wave during the explosion process. The maximum overpressure of the coal dust explosion under the weak ignition conditions in the tube was 70 kPa and the propagation velocity of the pressure wave along the tube was approximately 370 m/s. The minimum concentration for obtaining a coal dust explosion that propagated along the tube was 120 g/m³. The suppressing effects on the coal dust explosion of two different kinds of suppressing agents have been studied.     

Study of The Blast Waves from the Explosion of Nonspherical Charges

The blast wave patterns from the explosion of cylindrical charges are very complex and the pressure-time histories exhibit multiple shocks. The accurate assessment of the blast wave parameters (positive peak overpressure, duration, and the positive impulse) thus is not a simple task. In this paper a simple system is described for studying the blast waves from the explosion of small cylindrical charges together with comprehensive methods to analyse the experimental results. The assessment of the near-field/far-field behaviour also has been studied.     

Shock and detonation waves generated by a wire explosion in liquids and bubbled media

Parameters of shock waves generated by a wire explosion in a gas, liquid, and inert or reactive bubbled media in a vertical shock tube are measured. Problems of shock wave velocity measurements in a liquid and inert bubbled medium are discussed. Experimental data are compared with theoretical estimates. Excitation of self-sustained detonation in a chemically active medium by a short shock wave induced by a wire explosion is studied.     

Initiation of an explosion of a single bubble and bubble detonation

Interaction of a single chemically active bubble in water with acoustic waves is numerically studied within the framework of the model of a two-dimensional unsteady flow of an ideal compressible medium. The boundaries between the phases are explicitly identified. It is demonstrated that bubble explosion initiation can be determined by the character of bubble deformation. Nonsphericity of deformation and jet formation lead to an explosion even if the bubble does not collapse. The possibility of the bubble explosion in an expansion wave, transfer of detonation from one bubble to another, and, thus, emergence of bubble detonation is demonstrated.     

Explosion of Explosives in Subsurface Magazines and its numerical analysis

The subsurface magazine is a new type of magazine in Japan, which is defined as a magazine constructed underground and equipped with elevators of other transportation means. and is different from the usual tunnel type underground magazine. Explosions of explosives in model subsurface magazines were carried out. and explosion gases and shock waves blown out from their entrances were observed by schlieren photography. The blast overpressures were also measured by piezoelectric transducers. these external effects by explosion of explosives in the subsurface magazines were found to be less than those in the underground magazines. The above phenomena were simulated by numerical analysis using PISCES 2DELK code. Caluculated maximum overpressure and velocity of gases and shock waves were in fair agreement with their experimental values.