天然气气瓶爆炸危害的分析

通过对天然气气瓶所载气体爆炸能量及冲击波对人与建筑物危害程度的分析,提出了进行一步加强天然气气瓶安全防护措施的必要性.     

冲击波载荷对平面阵列天线电性能的影响

从机电学科交叉的角度,研究冲击波载荷作用下平面阵列天线结构塑性变形对天线电性能的影响.首先,根据爆炸冲击波的超压时程模型,采用弹塑性结构的瞬态有限元方法,获得冲击波载荷作用下平面阵列天线结构的塑性变形.然后,将结构塑性变形引入到平面阵列天线远场方向图表达式中,得到冲击波载荷作用下天线电性能的数学分析模型.最后,针对某X频段工作的平面阵列天线,分析了冲击波载荷对其增益损失、副瓣电平及波束指向的影响关系.数值分析结果可用来预测冲击波载荷作用后平面阵列天线可否正常工作.另外,文中的分析方法也可用于其他类型天线的冲击波载荷影响分析.     

冷旋压高压气瓶瓶底结构强度分析

以冷旋压高压气瓶瓶底结构为研究对象,气瓶材料为34CrMo4H高强度合金,采用有限元法,对各载荷工况条件下瓶底的应力分布进行分析,结合相关的强度设计标准对瓶底结构进行强度分析,并对高压气瓶瓶底结构进行了优化。结果表明:瓶底结构满足强度要求,所产生冷旋压气瓶的爆破压力远小于设计极限压力,且还有相当的安全裕量;在满足气瓶强度要求的条件下,提出了一种更为合理的冷旋压高压气瓶的瓶底结构,从而为冷旋压高压气瓶的优化改进提供了技术支撑。     

气瓶制造监督检验统一性的分析与讨论

随着我国经济社会的快速发展,气瓶在越来越多的领域得到了广泛应用。不同的分类标准下,气瓶所包含的种类有着明显区别。由于气瓶属于特种设备,因此各个领域对气瓶使用的质量、性能要求非常高。虽然国家陆续出台了关于气瓶制造方面的监督检验法律法规,但是这些法律法规的统一性尚存在很多问题。基于此,针对现有的关于气瓶检验监督的相应法律法规开展统一性分析和讨论,对提高气瓶制造质量具有重要的指导价值。     

气瓶水压试验方法的比较及应用分析

综合分析了气瓶在批量生产条件下,气瓶水压外测法和气瓶水压内测法的优缺点。通过改变气瓶水压内测法中受试瓶的试验状态,同时采用计算机控制技术,克服气瓶水压内测法试验受试验条件影响大的缺点,从而提高测量精度,以适合批量生产的条件。     

冲击波处理及冲击后退火对16MnR钢韧性的影响

了低爆压冲击波处理以及冲击波形变十退火处理后,１６ＭｎＲ钢冲击韧性的变化。结果表明,经冲击波处理后１６ＭｎＲ钢的预制裂纹样呈现韧化特征而缺口试样却呈现脆化特征。经退火后,材料的缺口和预制裂纹试样的呈现韧化倾向。相同变形量条件下,冲击波形变＋退火处理对材料性能的改善,明显高于冷压为＋退火处理对材料的作用。     

LNG车载气瓶支架强度分析及优化

运用Solid Works三维软件建立新型的LNG车载气瓶支架模型,导入分析软件ANSYS Workbench中,分别在三种不同工况条件下,进行强度分析,找出其中是否存在缺陷。结果表明,优化后的气瓶支架强度效果明显,结果合理,且与原有的气瓶支架相比,实现气瓶支架的轻量化,能为企业带来极大的经济效益。     

基于ISA总线的高压气瓶安全检测装置的研制

文中介绍了高压气瓶缺陷检测及安全评定装置的结构，系统组成及系统各部分的功能和作用，设计了双路40MSPS高速数据采集卡，该采集卡具有较高的数据采集质量，适用于各类瞬变信号的实时采集。建立了高压气瓶缺陷分析及安全评定模型，给出了部分软件的算法及详细设计方案。     

纤维环向缠绕复合材料气瓶冲击损伤容限研究

为研究纤维缠绕复合材料层CNG气瓶冲击后损伤容限问题,采用疲劳应变比率作为损伤变量,建立疲劳累积损伤模型;对气瓶缠绕层的冲击损伤剩余强度采用开孔等效计算方法,应用Nuismer—Whitney平均应力准则,关联疲劳累积损伤函数中的最大应力与拉伸载荷下的含孔层合板剩余强度的关系,建立适用于在疲劳载荷下的含孔层合板结构剩余强度的估算方法,用于复合材料CNG气瓶冲击剩余强度的预测。结果表明,文中提出的分析模型预测结果与专家提出的复合材料气瓶冲击损伤评定标准基本吻合。     

基于顺序耦合的火灾环境下气瓶热及力学响应数值模拟

火灾环境下,气瓶内流体介质的温度和压力及气瓶壁的温度不断地升高,可能导致气瓶爆炸。基于分区求解、边界耦合数值解法和流固耦合传热理论,采用计算流体力学软件FLUENT得到火灾环境的温度场、热流密度分布与气瓶的温度场及其内部介质的温度场、流场和压力场。然后根据顺序耦合思想,利用节点差值方法将FLUENT热边界无缝转化到有限元软件ANSYS中,继而进行热-应力分析,预测该钢质无缝气瓶爆破时间为6 min左右,对气瓶火灾应急方案的制定具有理论指导意义。     

Note: A table-top blast driven shock tube

The prevalence of blast-induced traumatic brain injury in conflicts in Iraq and Afghanistan has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. This paper describes the design and performance of a table-top shock tube that is more convenient and widely accessible than traditional compression driven and blast driven shock tubes. The design is simple: it is an explosive driven shock tube employing a rifle primer that explodes when impacted by the firing pin. The firearm barrel acts as the shock tube, and the shock wave emerges from the muzzle. The small size of this shock tube can facilitate localized application of a blast wave to a subject, tissue, or material under test.     

A study on impulsive sound attenuation for a high-pressure blast flowfield

The present work addresses a numerical study on impulsive sound attenuation for a complex high-pressure blast flowfield; these characteristics are generated by a supersonic propellant gas flow through a shock tube into an ambient environment. A numerical solver for analyzing the high pressure blast flowfield is developed in this study. From numerical simulations, wave dynamic processes (which include a first precursor shock wave, a second main propellant shock wave, and interactions in the muzzle blasts) are simulated and discussed. The pressure variation of the blast flowfield is analyzed to evaluate the effect of a silencer. A live firing test is also performed to evaluate four different silencers. The results of this study will be helpful in understanding blast wave and in designing silencers.     

Numerical Analysis and Verification of the Gas Jet from Aircraft Engines Impacting a Jet Blast Deflector

The process of the gas jet from aircraft engines impacting a jet blast deflector is not only a complex fluid–solid coupling problem that is not easy to compute, but also a safety issue that seriously interferes with flight deck environment. The computational fluid dynamics (CFD) method is used to simulate numerically the impact effect of gas jet from aircraft engines on a jet blast deflector by using the Reynolds-averaged Navier-Stokes (RANS) equations and turbulence models. First of all, during the pre-processing of numerical computation, a sub-domains hybrid meshing scheme is adopted to reduce mesh number and improve mesh quality. Then, four different turbulence models including shear-stress transport (SST) k-w, standard k-w, standard k-ε and Reynolds stress model (RSM) are used to compare and verify the correctness of numerical methods for gas jet from a single aircraft engine. The predicted values are in good agreement with the experimental data, and the distribution and regularity of shock wave, velocity, pressure and temperature of a single aircraft engine are got. The results show that SST k-w turbulence model is more suitable for the numerical simulation of compressible viscous gas jet with high prediction accuracy. Finally, the impact effect of gas jet from two aircraft engines on a jet blast deflector is analyzed based on the above numerical method, not only the flow parameters of gas jet and the interaction regularity between gas jet and the jet blast deflector are got, but also the thermal shock properties and dynamic impact characteristics of gas jet impacting the jet blast deflector are got. So the dangerous activity area of crew and equipments on the flight deck can be predicted qualitatively and quantitatively. The proposed research explores out a correct numerical method for the fluid–solid interaction during the impact process of supersonic gas jet, which provides an effective technical support for design, thermal ablation and structural damage analysis of a new jet blast deflector.     

不同气室充气容积对油气弹簧动态特性影响分析

以矿用宽体车前悬单气室油气悬挂缸为研究对象,对悬挂缸非线性动态特性进行了深入分析,建立了悬挂输出力数学模型,搭建了单气室油气悬挂缸AMESim仿真模型;在此基础上研究了工作参数对动载压力随行程变化的影响规律和悬挂系统的缓冲原理。结果表明:初始气室充气容积越大,达到额定动载压力时的行程长度越长;当悬挂行程恒定时,初始气室充气容积与悬挂输出力及刚度呈反比。以某型号悬挂缸为例,当预充气体积为1.25 L,预充气压力为5.2 MPa时,缓冲效果适中,且行程长度不宜超过67 mm。研究为产品设计及其使用寿命提供了理论依据及重要手段。     

多台高炉鼓风机拨风控制技术

介绍了适用于高炉供风系统的拨风控制技术，此技术有效地避免了因高炉鼓风机组故障突然停机而导致的高炉风口灌渣的严重事故。实际运行表明，应用效果良好。     

基于AMESim的气液增压缸的动态性能分析

分析气液增压缸的结构和工作原理,得出气液增压缸的数学模型,针对某公司生产的S830506D型号气液增压缸,运用AMESim建立一个工作周期内气液增压缸运行模型,并对该缸的动态性能进行仿真,分析气源压力、预压弹簧刚度、高压密封处过流面积对增压缸动态性能的影响。对气液增压缸的设计和选型有一定参考价值。     

Investigations of the watershield effect on blast waves: One and two-dimensional study

The object of this analysis is to investigate the mitigation effects of watershield on blast waves numerically. One application of current work is to resolve the design concerns for the ammunition storage facilities. To verify the numerical procedure using a multimaterial Eulerian finite element method, the results are compared with the available experimental data for detonation in a pressured tank, and the analytical predictions for air shocks. Features of the free-field detonation process are then studied from a series of one-dimensional simulations. The magnitude of peak pressure decreases and shock arrival time increases with increasing thickness of watershield. For design analysis, the case of two-dimensional axisymmetric geometry (a vertical) right-circular cylinder) with a central charge is also considered. The full process including initial detonation, shock wave propagation and reflection from the outer rigid boundary is examined. For the explosives immersed in water, the magnitude of peak pressure becomes smaller than those in air tank without watershield. At later time period, the average gas pressure left in the air tank is about 20 bar.     

基于SPH算法的驾驶室底部结构对爆炸冲击波响应数值仿真

针对地雷等简易爆炸装置在车辆驾驶室底部非接触爆炸问题,引入无网格光滑粒子流体动力学(Smoothed particle hydrodynamics,SPH)算法模拟爆炸冲击波作用下车辆底部结构的响应。以四边约束靶板为研究对象,分析靶板在爆炸冲击下的能量、应力变化和破坏形态,通过与传统的任意拉格朗日欧拉(Arbitrary Lagrangian-Eulerian,ALE)固流耦合分析法和经验公式计算结果对比,验证SPH算法应用于处理此类问题的可行性;利用SPH算法对爆炸冲击波作用下驾驶室底部结构进行数值仿真,分析车辆底部的油箱、电瓶支架、驾驶室地板、车架等关键结构的冲击响应,并与试验做出对比验证。仿真结果表明,基于SPH算法的爆炸仿真分析具有精度较高、建模简单、耗费计算资源少等优势,能够应用于爆炸冲击波作用下驾驶室底部板壳结构的响应研究,并为驾驶室底部结构抗爆炸设计提供参考。