燃气发生器低频非稳态燃烧统计分析

针对冲压发动机地面试验需求,设计燃气发生器,通过试验统计研究其燃烧稳定性特征。结果表明:该燃气发生器发生低频非稳态燃烧的概率为32.7%,存在两种振荡形态。一种存在振荡主频,即低频不稳定燃烧;另一种没有主频,燃烧形态为粗暴燃烧。粗暴燃烧发生概率高且与余氧系数存在较强的相关性,低频不稳定燃烧发生概率低。两种形态的振荡能量分布位置不同。     

温度及密封性对改性双基推进剂中安定剂的影响

采用热加速寿命试验和安定剂质量分数测试试验（气相色谱），确定改性双基推进剂在不同温度、不同贮存条件下安定剂间苯二酚（Res）和中定剂（C2）质量分数的变化规律，分析安定剂质量分数变化的原因，得出不同温度下密封性对此类推进剂中安定剂质量分数的影响规律。     

惰性气体灭火系统减压孔板设计计算方法研究

选择DN40及其三种规格孔径的IG100惰性气体灭火系统减压孔板为研究对象,采用fluent数值计算软件进行计算,得到压比-流量特性曲线及计算公式,在设计计算时可直接根据压比-流量特性曲线选择合理的减压装置,为此类设计提出了一种新的计算研究手段。     

加油站消防安全对策及消防设计探讨

近年来,加油站的数量不断增多,规模不断扩大,对加油站的消防安全要求也不断提高。详细分析了加油站的火灾、爆炸危险性;论述了加油站预防火灾、爆炸事故的对策,并对加油站的消防安全设计提出了几点看法。     

空气/煤油/水燃气发生器点火特性试验研究

燃气发生器是超燃冲压发动机地面试验系统中的关键设备,为提高系统安全性和经济性设计了空气/煤油/水燃气发生器,在富燃状态下进行了一系列点火试验,试验结果表明：该型燃气发生器,实现可靠点火的余氧系数下限为0.51;水的加入使得化学反应速率和火焰传播速度降低,燃气发生器点火和火焰稳定困难,提高余氧系数可以提高点火可靠性。同时水的加入容易引起燃烧不稳定,通过提高余氧系数可消除低频不稳定燃烧。     

Terrorism,insurgency, kidnapping,and security in Africa's energy sector

Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).     

Ablation characteristics of insulator under high-temperature gas dual-pulse erosion

This study numerically simulated and investigated the flow field characteristics of a typical dual-pulse solid rocket motor with a soft pulse separation device through thermal insulation ablation under high-temperature dual-pulse erosion. The ablation rate of ethylene -propylene-diene monomer (EPDM) insulator was measured after the experiment. Experimental results were analyzed through scanning electron microscopy and microcomputed tomography. The ablation mechanism of the EPDM insulator under the operation conditions of a dual-pulse solid rocket motor was evaluated by analyzing the results. The results reveal that the internal flow field of the motor with a soft pulse separation device is uniform. The original charred layer existing on the EPDM insulator surface in the first pulse combustor is the decisive factor affecting the final ablation rate of the dual-pulse motor during the second pulse operation, and the ablation characteristic region is easily formed with the exfoliation of the charred layer. The ablation rate difference of the insulator increases with gas velocity.     

三元混合气体爆炸极限实验研究

瓦斯爆炸是煤矿灾害事故最主要的因素。瓦斯是以CH4为主,常含有CO2、CO、H2S、C2H4、C2H6、H2、SO2等的多元混合可燃性气体。随着各组分配比的不同,瓦斯的爆炸极限不同,呈现的火灾爆炸危险性也不同。利用HY12474型爆炸极限测定仪研究煤矿开采区常见的可燃气体混合物爆炸极限随组分配比变化的情况。通过对三组分不同配比混合气体的爆炸极限的测试,采用Taylor多项式,拟合出了常压下三元气体混合物的爆炸极限随组分配比变化的经验计算公式,并通过实验数据进行了验证,表明经验公式计算结果与实验数据很好吻合,具有工程应用价值。     

探火管灭火装置在电气设备火灾防控中的应用

针对电气设备火灾防控难度大的问题,分析了传统气体灭火系统在电气设备火灾防控中存在的缺陷,介绍了探火管灭火装置的基本构成,分析了在特定的电气设备火灾防控中,采用探火管灭火装置替代传统气体灭火系统的优势,并给出探火管灭火装置实际应用案例,探讨了探火管灭火装置的应用前景。     

Ukrainian and Belorussian dimensions of Turkmenistan foreign policy: small states in a multipolar world

As the USA continues to decline both in relative and absolute terms, the global order emerges where no center of power exists. This creates a complicated and instable geopolitical situation where small states could act behind the back of the great powers. The relationship between Turkmenistan and Ukraine is the example of this sort of relationship. Whereas Ukraine wants to get cheap gas, Turkmenistan wants to find the way to sell its gas to the West. It looks as though both countries pay little attention to Russian objection and act without direct help from either the USA or other great powers.