Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate

Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.

Enhancing Fire Safety in Commercial Vehicles: Assessing the Efficacy and Advantages of Exploding Fire Extinguishing Balls

Fire incidents in commercial vehicles pose significant risks to passengers, drivers, and cargo. Traditional fire extinguishing systems, while effective, may have limitations in terms of response time, coverage, and human intervention [1]. This study investigates the efficacy of a novel fire suppression technology—the Exploding Fire Extinguishing Ball (EFEB) —as an alternative and complementary fire safety solution for commercial vehicles. The research employs a multidisciplinary approach, encompassing engineering, materials science, fire safety, and human factors analysis. A systematic literature review establishes a comprehensive understanding of existing fire suppression technologies, including EFEBs. Subsequently, this study analyzes the unique features of EFEBs, such as automatic activation, as well as manual activation upon exposure to fire, and their potential to provide rapid, localized, and autonomous fire suppression. The study presents original experimental investigations to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. Experiments include controlled fires in confined spaces and dynamic simulations to emulate real-world fire incidents. Data on activation times, extinguishing capability, and coverage area are collected and analyzed to compare the efficacy of EFEBs with traditional fire extinguishing methods. Furthermore, this research shows the practical aspects of implementing EFEBs in commercial vehicles. A feasibility study examines the integration challenges, cost-benefit analysis, and potential regulatory implications. The study also addresses the impact of EFEBs on vehicle weight, stability, and overall safety. Human factors and user acceptance are crucial elements in adopting new safety technologies. Therefore, this research utilizes an experimental design to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. This dissertation presents original controlled experiments to emulate real-world fire incidents, including controlled fires in confined spaces and dynamic simulations. The experimental approach ensures rigorous evaluation and objective insights into EFEBs’ potential as an autonomous fire suppression system for commercial vehicles. This includes the perspectives of drivers, passengers, fleet operators, insurance agencies, and regulatory bodies. Factors influencing trust, perceived safety, and willingness to adopt EFEBs are analyzed to provide insights into the successful integration of this technology. The findings of this research will contribute to the knowledge of fire safety technology and expand the understanding of the applicability of EFEBs in commercial vehicles.

Deep-Hole Inner Diameter Measuring System Based on Non-contact Capacitance Sensor

A precise aperture measuring system of small deep holes with capacitance sensors is presented. Based on the working principle of non-contact capacitance sensors, influence of the edge effect of gauge head is studied, and one capacitance sensor for measuring the aperture of the small blind holes or through holes is introduced. The system is composed of one positioning device, one aperture measuring capacitance sensor, one measuring circuit, and software. This system employs visual CCD and two-dimensional mic...

Effectiveness analysis of methane-drainage by deep-hole controlled pre-splitting blasting for preventing coal and gas outburst

In the study of the application effectiveness of deep-hole controlled pre-splittingblasting technology,it was found through laboratory micro test and field study on a mine insouth China that under the technology,coal masses produce many irreversible cracks.Afterblasting,the nearer the distance from blasting hole,the larger the BET surface areaand volume ratio of the infiltration pore are;they increased by 11.47%and 5.73%,respectively.The coefficient of air permeability is increased 4 times.After 3 months,the gasdrainage rate was increased by 66%.In the first 15 days,the cumulative pumped gas was1.93 times of blasting before.The average absolute gas emission decreased by 63.46%.Experimental results show that deep-hole controlled pre-splitting blasting not only preventscoal and gas outburst,but also gives good economic results.

Numerical simulation and experiment analysis of improving permeability by deep-hole presplitting explosion in high gassy and low permeability coal seam

Created a new damage model for explosive for LS-DYNA3D,taking advantageof the Taylor method aimed at the high gassy and low permeability coal seam,and numericallysimulated and analyzed the deep-hole presplitting explosion.The entire processof explosion was represented,including cracks caused by dynamic pressure,transmissionand vibration superposition of stress waves,as well as cracks growth driven by gas generatedby explosion.The influence of the cracks generated in the process of explosion andthe performance of improving permeability caused by the difference of interval between.explosive holes were analyzed.A reasonable interval between explosive holes of deepholepresplitting explosions in high gassy and low permeability coal seams was proposed,and the resolution of gas drainage in high gassy and low permeability coal seam was putforward.

Numerical simulation of deep-hole resistivity anomaly caused by drilling construction in Xinfengjiang geoelectric station

The Xinfengjiang reservoir in Guangdong Province is one of the large reservoirs that have triggered earthquakes of magnitude greater than 6.Numerous earthquakes have occurred since the impoundment of the reservoir,making it one of the most active seismic zones in south China.In 2015,a set of deep-hole resistivity anomalies was observed in the Heping geoelectric station in Dongyuan county,located near the Xinfengjiang reservoir.After a field investigation,we found that a planned well drilling construction of new measuring channels was being carried out during that corresponding period of time.After careful comparison and analysis on the basis of the collected raw data,we had a reason to believe that drilling construction,rather than the inducement of the Xinfengjiang reservoir,was the main culprit for those unusual georesistivity values.So as to verify the above conjecture,we constructed a series of 3D finite element models based on the geological and hydrological infor-mation around Heping station and analyzed the drilling disturbances,respectively.Some significant conclusions were finally drawn according to the precise numerical simulation.This study gives a good example by combining numerical simulation with engineering practice as a way to understand the root cause of georesistivity anomalies in reality.

某直列式点火器双路瞎火故障分析与改进

针对某直列式点火器在低温点火试验中出现的双路冲击片点火管瞎火问题,进行了故障定位及原因分析,提出了改进措施并对其有效性进行了试验验证。结果表明:造成双路瞎火故障的原因是点火器转接件焊点异常处的气体间隙弧光放电;提出将2个回路的触发信号时间间隔调整为50μs,按照HB 7262航空产品电装工艺的相关规定细化电装工艺,增加对能量传输通道的介质耐压检测等改进措施。验证试验表明采取改进措施后,消除了弧光放电现象,点火器内的2个爆炸箔表面均有明显的电爆炸痕迹。

某露天矿山采选工艺联合优化

某大型露天矿以氧化矿为主,随着开采不断深入,氧化矿出矿量逐年减少,原生矿出矿量逐年增加。为进一步提高资源利用率及选矿台效,开展了采场爆破设计优化、破碎参数及设备能力匹配、流程改造实施等一系列技术攻关,实现了破碎流程的最优粒度供给,在保障以爆代破的同时,实现挂帮矿有效回收利用。同时,磨矿分级单元的优化使得氧化矿加工流程处理能力大幅提升,“磁选-重选”给矿提前抛尾,大幅提高了入选矿石性质,流程循环量的降低,推动生产效能进一步提升,为企业提产增量、降本增效提供了有力支撑。

BPN组分粒径对Slapper-BPN型EFDI发火感度的影响

为了研究硼/硝酸钾(BPN)组分粒径对Slapper-BPN型爆炸箔爆燃点火器(EFDI)发火感度的影响,设计并制备了由不同粒径的硼粉和硝酸钾组成的多个BPN配方,采用激光粒度仪表征了硼粉的粒径,讨论了硼粉粒径数量分布和体积分布的特点;通过扫描电镜(SEM)获得硝酸钾粒径对BPN药剂界面形貌的影响;根据差示扫描量热法(DSC)数据,计算了不同配方BPN的指前因子、表观活化能、最低热解温度和热爆炸临界温度,分析了BPN组分粒径对其动力学性能的影响;根据兰利法获得了不同配方BPN的临界发火电压及标准误差,讨论了BPN动力学性能和药剂界面形貌对其发火感度的影响。结果表明,BPN组分粒径主要从BPN的热分解性能和药柱界面形貌影响EFDI发火感度;BPN组分粒径变大,会使BPN药剂的最低热解温度变高,从而降低了EFDI发火感度;BPN组分粒径变小,改变了BPN药柱界面形貌,会使BPN药柱颗粒堆积更密实,减小药剂颗粒空隙,阻碍BPN的传火传热通道,在低密度装药条件下,会明显降低EFDI发火感度。因此,硼粉粒径一致性对低密度BPN发火感度的标准差具有一定影响。

氩气中铝丝电爆炸空间形态不均匀现象及其抑制方法

铝丝电爆炸法制备纳米粉体具有低成本、高效率、产物纯度高且粒度分布可控等优势,其扩散阶段空间形态均匀性是影响纳米铝粉品质的关键因素。为此设计并搭建了铝丝电爆炸实验系统,可实现包括激光成像、分幅成像与辐射光谱分析的超快光学诊断。观测到铝丝电爆炸扩散阶段出现的等离子体晕层、“纺锤形”结构、“拉链状”结构、分层结构、局部热点、缺口、残留丝核等空间形态不均匀现象,并揭示了其产生原因包括氛围气体放电、径向非均匀汽化、热力学不稳定性、磁流体力学不稳定性。建立了基于自辐射图像的空间形态均匀性量化表征方法与判别准则。研究获得了气压与电流参数对阻性阶段及沉积能量特性的影响规律,并提出了空间形态不均匀性的抑制方法——增加气压与提高电流上升率,最终确定了可实现均匀电爆炸的参数选取方法。

多点起爆技术及应用研究进展

综述了爆炸网络多点起爆技术和直列式多点起爆技术的发展,介绍了爆炸网络多点起爆技术的多点同步爆炸网络和多点逻辑爆炸网络的应用现状,分析了两者的优势及不足;对比了直列式多点起爆技术的国内外研究现状,讨论了多点起爆点数、起爆方位参数对多点起爆系统性能的影响,指出多点起爆技术未来研究方向为:多点起爆精确控制方法研究,多点起爆装置模块化与集成化研究,低成本多点起爆技术研究,复杂环境下多点起爆系统安全性与可靠性研究。

集成化Al膜爆炸箔起爆器的制备与性能研究

为了提高爆炸桥箔的换能效率以及爆炸箔起爆系统的起爆能力,采用Al膜作为爆炸箔金属桥膜,开展了集成化Al膜爆炸箔起爆器的制备工艺研究。对桥区尺寸为0.2~0.4 mm、厚度为5~8μm的Al桥电爆炸性能进行测试,并在此基础上测试了驱动飞片速度。研究结果表明:200 W溅射功率、20 sccm氩气流速是制备Al膜的最佳工艺条件;1 000 V电压条件下,厚度为6μm、桥区尺寸为0.35 mm×0.35 mm的桥箔电爆炸时爆发功率最大,相比相同输入能量的Cu桥,爆发功率提高14.3%,电能沉积率提高9.63%;桥区尺寸在0.2~0.4 mm时,飞片速度随桥区尺寸的增大而逐渐减小,桥区厚度为7μm时飞片速度最大,1 000 V充电电压下达到4 100 m·s^(-1),高出Cu桥7.89%。

全谷物包埋爆爆珠植物饮配方的研制

以全谷物玉米和紫薯为爆爆珠制作原料,采用单因素-正交试验对全谷物包埋爆爆珠植物饮的配方进行研究和优化。结果表明,玉米爆爆珠对全谷物包埋爆爆珠植物饮品质影响最大,其次是柳芽茶添加量,白砂糖添加量对全谷物包埋爆爆珠植物饮品质影响最小。制作全谷物包埋爆爆珠植物饮的最佳配方为柳芽茶添加量4.0 g,纯净水添加量100 mL,玉米爆爆珠添加量6.0 g、紫薯爆爆珠添加量4.0 g、白砂糖添加量4.0%。

MEMS集成爆炸箔芯片的发火性能研究

为了实现高速飞片输出和爆炸箔起爆器(Exploding Foil Initiator, EFI)低能发火,依据EFI工作原理,进行Cu桥箔电热仿真、PC(聚氯代对二甲苯)飞片冲击作用参数计算和SU-8加速膛结构确定。基于结构设计参数,采用微机电系统(Micro-Electro-Mechanical System, MEMS)工艺实现了爆炸箔芯片一体化批量制备,并开展了MEMS集成爆炸箔芯片的桥箔电爆特性、飞片实时速度和冲击起爆性能测试。结果表明:基于小尺寸桥箔结构在较低放电电压下就能够获得较高的飞片速度,并且在加速膛口飞片速度达到峰值速度的96%以上;冲击起爆HNS-IV药柱的最低发火条件为0.22μF/1 100 V,实现了EFI低能发火。

某铅锌矿厚大矿体矿柱回收方案研究与应用

东升庙铅锌矿对回收矿柱资源开展了大量的工作,通过多年的实践逐渐形成了一套较为完整的资源回收和采空区治理体系。针对11-1号矿体02间柱一侧为胶结充填一侧为空区的状态,采用强制崩落上部围岩与采掘废石联合充填空区、在覆岩下逐排后退式回收方案,成功回收矿产资源20.98万t,取得了间柱综合回收率75.62%,贫化率23.48%的较好指标。

加速膛参数对换能元飞片速度的影响

飞片速度是冲击片雷管能否可靠起爆的一个关键因素,为了深入研究加速膛参数对飞片速度的影响,分别通过实验和数值模拟方法对飞片速度的影响因素进行分析。采用磁控溅射技术设计制备了一种膜层厚度为0.5/0.5/2μm,尺寸为0.15 mm×0.15 mm的TiW/Ni/Au复合薄膜爆炸箔。在激励条件为0.1μF、1200 V下,选用密度为1.45 g·cm^(-3),厚度为25μm的聚酰亚胺飞片,利用光子多普勒速度测试技术测量了不同加速膛参数的飞片速度。研究结果显示:在相同孔径条件下,当加速膛厚度分别为0.3,0.4,0.5,0.6 mm时,随着加速膛厚度的增加,飞片速度先增后减,在厚度为0.4 mm时达到最高值;在相同厚度条件下,当加速膛孔径分别为0.15,0.23,0.3,0.35,0.45 mm时,飞片速度随孔径增加而降低,其中孔径为0.15 mm时速度最高;此外,在相同孔径和厚度下,飞片经过聚酰亚胺和陶瓷两种材质的加速膛测试得到的速度变化趋势和数值相近,而聚酰亚胺具有较高的强度和韧性,成本更低,因此可替代陶瓷作为加速膛材料。同时采用数值模拟方法重新拟合了适用于TiW/Ni/Au复合薄膜的飞片速度经验公式,验证结果表明,计算结果与实验数据的偏差均在2.5%以内。

Explodator模型特性的数值模拟

本文采用 Explodato r模型解释 B—Z 反应中的时间振荡现象,并利用计算机进行了数值模拟,其结果符合实验事实.

二次电池化成设备的防爆设计

通过对二次电池化成设备的防爆设计,减少设备危险区域,提高二次电池化成工序的安全性能,促进电池检测设备达到全球化安全认证的标准。以爆炸性环境系列标准为依据,结合化成工艺时序表,进行了异常和极端异常情况的电解液挥发浓度计算,分析了点燃源风险和危险区域。对设备的排风风道和风量进行仿真优化分析,通过软件系统监控设备的排风、环境温度、烟雾、液位、真空压力、电池充放电电压、电流、温度等参数,并进行及时地反馈与控制。详细规范了防爆监控相关元器件的安装、接地、隔离、校准及点检的要求。通过系统与规范的防爆设计使设备的安全区增大,危险点减少,提高了设备的安全性能。采用烟雾发生器对样机设备排风风道进行测试,验证表明设备的排风排烟效果与仿真一致,库位内无危险气体残留死角存在,满足防爆设计要求。分析、优化和规范方法对电池检测设备的防爆设计具有现实的指导意义。

A micro-chip exploding foil initiator based on printed circuit board technology

Conventional exploding foil initiator (EFI) in ignition or detonation applications hosts many performance advantages, but was hindered by the bulky, inaccurate, inefficient and expensive shortcomings. We highlight a novel micro-chip exploding foil initiator (McEFI) using printed circuit board (PCB) technology. The structural parameters were determined based on energy coupling relationship at the component interfaces. Next, the prototype McEFI has been batch-fabricated using PCB technology, with a monolithic structure of 7.0 mm (l) × 4.5 mm (w) × 4.0 mm (δ). As expected, this PCB-McEFI illustrated the successful firing validations for explosives pellets. This paper has addressed the cost problem in both military munitions and civil markets wherever reliable, insensitive and timing-dependent ignition or detonation are involved.

Piezoelectric responses of brittle rock mass containing quartz to static stress and exploding stress wave respectively

The electromagnetic emission(EME) induced from the rock containing piezoelectric materials was investigated under both static stress and exploding stress wave in the view of piezoelectric effect. The results show that the intensity of the EME induced from the rock under static stress increases with increasing stress level and loading rate; the relationship between the amplitude of the EME from the rock under different modes of stress wave and elastic parameters and propagation distance was presented. The intensity of the EME relates not only to the strength and elastic moduli of rock masses,but also to the initial damage of the rock. The intensity of EME induced by stress wave reaches the highest at the explosion-center and attenuates with the propagation distance. The intensity of EME increases with increasing the elastic modulus and decreases with increasing initial damage. The results are in good agreement with the experimental results.