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1.
基于云分类器的液体火箭发动机故障诊断方法   总被引:2,自引:0,他引:2       下载免费PDF全文
本文首先将液体火箭发动机故障诊断问题转化为故障特征的模式分类问题,然后针对当前模式分类方法难以处理不确定性信息、属性特征空间的划分过硬等缺陷,结合云模型和云变换研究,提出了一种基于云分类器的液体火箭发动机起动过程故障诊断方法。历次试车数据的验证结果表明,该方法能够及时准确识别发动机起动工作过程中的故障模式。  相似文献   

2.
本文介绍了标准化项目炸药热安定性试验方法的研究情况,项目采用DSC研究测试了几种工业炸药放热分解反应的起始温度和峰顶温度,考察了不同试验条件下试样DSC曲线的差异。分别用Kissinger及Ozawa法计算了二级煤矿许用乳化炸药的动力学参数。结果表明:试样量及气氛对试验结果影响较大,标准中规定的条件恰当。  相似文献   

3.
液体发射药火炮及其发展趋势   总被引:2,自引:0,他引:2  
阐述了液体发射药的分类和特点,以及液体发射药火炮的研制概况、发射原理,进而分析了液体发射药火炮的性能特点和发展趋势。认为液体发射药取代传统的固体发射药,具有很高的军事价值,它将应用于未来信息化战争需要的新概念火炮,同时引起新的火炮技术变革。  相似文献   

4.
本文对比介绍了弹道臼炮法、铅垮扩孔法、爆破漏斗法、水下爆破法、弹道摆试验等几种常用作功能力测定标准方法、原理、适用范围和表征方法,及其在实际应用中存在的局限性。最后提出了一种作功能力测试新方法——弹道抛掷法。  相似文献   

5.
功能化离子液体的合成表征及其作为润滑剂的性质   总被引:3,自引:1,他引:2  
通过两步法合成了含酯基官能团的咪唑类离子液体1-乙酸乙酯基-3-甲基咪唑四氟硼酸盐,用核磁共振、红外光谱、元素分析对其进行了结构表征,证明了该合成方法的可靠性;对功能化离子液体的基本物化性质、熔点、热稳定性及其作为润滑剂的粘温性、蒸发损失、金属腐蚀性等进行了全面研究,并选择了含有相同烷基的1-丁基-3-甲基咪唑四氟硼酸盐传统离子液体进行对比,发现官能团的引入,使传统烷基咪唑类离子液体展现出不同的特性,同时发现两种离子液体均对金属表面有较强的腐蚀作用,为进一步开展功能化离子液体的摩擦学研究打下了基础。  相似文献   

6.
两种单基发射药灌注成型为凝胶炸药研究   总被引:1,自引:0,他引:1  
对14/7和22/1两种单基发射药灌注成型为凝胶炸药进行了初步的试验研究,并对生成的凝胶炸药进行了威力和猛度测试。结果表明,可以利用高分子含水材料与氧化剂将废弃的发射药转化为凝胶民用炸药,通过调整装药直径,可获得一定的威力和猛度。  相似文献   

7.
分析了现有战场目标识别技术存在的问题,提出了基于数据挖掘的战场目标综合识别总体框架,对目标识别知识表示、目标特征知识挖掘、作战模式知识挖掘以及目标综合识别智能化推理等关键技术进行了研究,并说明了各关键技术在战场目标识别中的应用示例,可为提高战场目标识别的自动化、智能化水平提供借鉴。  相似文献   

8.
从战术计划识别的应用领域出发,以典型海战想定为背景,分析了水面舰艇编队战术计划识别的过程与特点,论述了实际水面舰艇编队战术计划识别所需的数据、模型、信息和相关知识。在仿真案例中,实现了在不完全观察条件下敌我对抗过程中对敌不同阶段计划意图的推理和识别,并通过和领域专家、指挥员及专业学员人工识别结果相对比,论证了识别结果的有效性和准确度。  相似文献   

9.
本文以膨化硝铵炸药标准为主,阐述行业标准制定以及行业标上升为国标过程中,标准制定的需求、标准主要内容、标准实施途径和项目研究的可行性。同时,阐述了制定过程中某些强制性内容和理由、标准试验方法中某些研究工作,以及民爆器材标准化工作研究中的几点体会。  相似文献   

10.
最近看到很多关于“姆潘巴现象”的文章,“姆潘巴现象”又名“姆潘巴效应”,指在同等体积、同等质量和同等冷却环境下,温度略高的的液体比温度略低的液体先结冰的现象。  相似文献   

11.
《防务技术》2022,18(11):1945-1959
Primary explosives are utilized as a reliable initiator for secondary explosives in an extensive range of military and civilian operations. Heavy–metal–based primary explosives are moderate performing, more sensitive, and environmentally hazardous, posing a direct and indirect threat to health and safety. Therefore, heavy–metal–based primaries have been replaced by environment-friendly metal-based primary explosives, such as potassium complexes. This review presents not only a summary of the current progress of new-generation potassium-based primary explosives and their methods of preparation, energetic properties, and applications, but also a further comparison with traditional primary explosives. In addition, this work discusses the necessity of heavy metal–free primary explosives and the major challenges faced in replacing traditional primary explosives.  相似文献   

12.
Heterocyclic skeleton (Azoles) and different energetic groups containing high performing explosives are highly emerged in recent years to meet the challenging requirements of energetic materials in both military and civilian applications with improved performance. For this purpose tetrazole (Azole) is identified as an attractive heterocyclic backbone with energetic functional groups nitro (-NO2), nitrato (-ONO2), nitrimino (-NNO2), and nitramino (–NH–NO2) to replace the traditionally used high performing explosives. The tetrazole based compounds having these energetic functional groups demonstrated advanced energetic performance (detonation velocity and pressure), densities, and heat of formation (HOF) and became a potential replacement of traditional energetic compounds such as RDX. This review presents a summary of the recently reported nitro-tetrazole energetic compounds containing poly-nitro, di/mono-nitro, nitrato/nitramino/nitrimino, bridged/bis/di tetrazole and nitro functional groups, describing their preparation methods, advance energetic properties, and further applications as high-performing explosives, especially those reported in the last decade. This review aims to provide a fresh concept for designing nitro-tetrazole based high performing explosives together with major challenges and perspectives.  相似文献   

13.
《防务技术》2020,16(2):290-298
In order to give the energy output structure of typical explosives near-ground explosion in real ground conditions, the free-field shockwave, ground reflection shockwave and Mach wave overpressure time history of composition B explosive, RDX explosive and aluminized explosive were measured by air pressure sensors and ground pressure sensors. The shape of the free-field shock wave, ground reflection shock wave, and Mach wave and explosion flame were captured by high-speed camera. The experimental results show that, at the same horizontal distance from the initiation point, the peak overpressure of explosive shock wave of composition B explosive, both in the air and on the ground, is less than that of RDX and aluminized explosives. At a distance of 3.0 m from the initiation point, the peak overpressure of aluminized explosives is slightly less than that of RDX explosives. Owing to the exothermic effect of aluminum powder, the pressure drop of aluminized explosives is slower than that of RDX explosives. At 5.0 m from the initiation point, the peak overpressure of aluminized explosives is larger than that of RDX explosives. At the same position from the initiation point, among the three kinds of explosives, the impulse of aluminized explosives is the maximum and the impulse of composition B explosives is the minimum. With the increase of the horizontal distance from the initiation point, the height of Mach triple-points (Mach steam) of the three explosives increases gradually. At the same horizontal distance from the initiation point, there is poorly difference in the height of Mach triple-points between aluminized explosive and RDX explosive, and the height of Mach triple-points of composition B explosive is much smaller than that of other two explosives. The maximum diameter and duration of the fireball formed by aluminized explosives are the largest, followed by composition B explosive, and the maximum diameter and duration of the fireball formed by RDX explosive are the smallest.  相似文献   

14.
《防务技术》2020,16(3):642-650
This work aims to research the effects on the early responses of the air-backed plate subjected to the loading generated by the underwater explosion with aluminized explosives. The loading characteristics of underwater explosion for ideal explosive (TNT), aluminized explosives (RS211 and RBUL) are obtained experimentally. The tested aluminized explosives have different energy output compared with TNT. Based on the Taylor plate theory, the early responses of the air-backed steel plate affected by the measured loading is analyzed. The analytical results indicate that the pressure curve of the shock wave within 1 time decay constant is the main factor affecting the kick-off velocity of the plate when cavitation occurring. The velocity responses of the plate produced by the loading of RS211 and RBUL are obviously different with that of an equivalent TNT charge, which also indicates validity and suitability should be noticed in the case of substituting TNT for aluminized explosives. Moreover, the uncertainties in the responses of the plate produced by RS211 and RBUL are much larger than TNT.  相似文献   

15.
A common criticism levelled at successive governments of the Republic of Ireland during the Northern Ireland ‘Troubles’ was their alleged inactivity in the face of a ferocious Provisional IRA campaign. Such criticisms were based in large part on the perception of the southern state as a supply base for militant republicanism. The Republic was undoubtedly a formidable logistics hinterland for such militants. However, criticisms of the reactions of authorities in the south are unfair. This article considers the explosives capabilities of the IRA during the first six years of their campaign. It does so with reference to their attempts to obtain commercial explosives as well as measures employed by them to obtain homemade explosives. The article also considers countermeasures employed by the southern government and reveals the extent to which they sought to shut down IRA capabilities in the south. It is argued that, ultimately, the IRA's campaign in this regard could only be contained and never unilaterally halted.  相似文献   

16.
This paper reviews the achievements in the field of synthesis of new thermally resistant explosive compounds in the years 2009 through 2019. The performance characteristics of these compounds (sensitivity, thermal decomposition parameters, and detonation parameters) were compared with those of 1,3,5-triamino-2,4,6-trinitrobenzene, which still seems to be an unrivalled model of a thermally resistant and generally low-sensitivity explosive material. New thermally stable explosives (TSEs) were found among macromolecular compounds with tri- and dinitrophenyl groups, nitro and amine-nitro derivatives of azoles, and polynitro derivatives of calixarenes. Some of them match TATB in terms of thermal resistance and additionally have higher detonation parameters.  相似文献   

17.
《防务技术》2020,16(2):316-324
This research aims to contribute to the safe methodology for additive manufacturing (AM) of energetic materials. Coating formulation processes were investigated and evaluated to find a suitable method that may enable selective laser sintering (SLS) as the safe method for fabrication of high explosive (HE) compositions. For safety and convenience reasons, the concept demonstration was conducted using inert explosive simulants with properties quasi-similar to the real HE. Coating processes for simulant RDX-based microparticles by means of PCL and 3,4,5-trimethoxybenzaldehyde (as TNT simulant) are reported. These processes were evaluated for uniformity of coating the HE inert simulant particles with binder materials to facilitate the SLS as the adequate binding and fabrication method. Suspension system and single emulsion methods gave required particle near spherical morphology, size and uniform coating. The suspension process appears to be suitable for the SLS of HE mocks and potential formulation methods for active HE composites. The density is estimated to be comparable with the current HE compositions and plastic bonded explosives (PBXs) such as C4 and PE4, produced from traditional methods. The formulation method developed and understanding of the science behind the processes paves the way toward safe SLS of the active HE compositions and may open avenues for further research and development of munitions of the future.  相似文献   

18.
19.
《防务技术》2022,18(11):1979-1999
A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum (Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed, and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction (diffusion and kinetic) between the Al powder and the detonation products; the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.  相似文献   

20.
研究了在压剪加载下炸药这类粘塑性介质中剪切带的形成与发展。提出了一种反映炸药装药中剪切带形成和发展的计算方法,并分析了剪切带发展变化特性与炸药起爆的关系  相似文献   

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