含团聚硼富燃料推进剂的能量特性及燃烧性能

用最小自由能计算程序计算了含硼富燃料推进剂的能量性能,探讨了不同压力时硼粉的质量分数对富燃料推进剂能量性能的影响,采用靶线法和化学滴定法研究了富燃料推进剂的燃烧特性和燃烧残渣中硼粉的燃烧效率。结果表明,随着硼粉含量的增加,推进剂的能量增大;大粒径的团聚硼对富燃料推进剂的燃速和压强指数影响较大,随着团聚硼含量的增加,推进剂的燃速提高;含硼富燃料推进剂中的硼粉燃烧后单质硼和硼化物的摩尔比发生了明显的变化,无定形硼粉经团聚后燃烧效率明显提高。     

含硼富燃料推进剂的技术现状与发展趋势

综述了国内外在硼粒子的点火、燃烧性能,硼粉的包覆、团聚造粒技术,硼粉处理对配方性能的影响,含硼富燃料推进剂配方及性能测试表征手段等方面的研究进展。总结了国内外含硼富燃料推进剂工程化应用的现状和存在的差距。     

DNTF基含硼和含铝炸药的水下能量

理论计算了DNTF基含硼和含铝炸药的爆炸性能参数,通过水下能量及爆热测试研究了它们的能量特性。结果表明,含硼质量分数15%的DNTF基炸药水下能量可达到2.1倍TNT当量,并出现最大值。含铝质量分数10%-50%的DNTF基炸药的水下能量随铝含量的增加呈上升趋势,其最大值可达到2.67倍TNT当量。当铅或硼的质量分数低于18%时,含硼DNTF炸药的能量高于含铝炸药。硼铝联用,也可获得较好的能量特性。     

温压炸药耗氧效应的实验研究

为了评估温压炸药的能量释放效率,通过理论计算和试验测试,得到塑料黏结炸药(PBX)及温压炸药的单位质量耗氧量、绝对耗氧量和爆炸罐中炸药的最佳弥散浓度,依据实验数据评估了炸药的能量释放效率。结果表明,温压炸药的弥散浓度在0.84g/L时爆炸耗氧量最大,其单位质量试验耗氧量是PBX的1.55倍,能量释放效率是PBX的1.13倍。     

DNTF基含硼和含铝炸药的水下能量

理论计算了DNTF基含硼和含铝炸药的爆炸性能参数,通过水下能量及爆热测试研究了它们的能量特性.结果表明,含硼质量分数15%的DNTF基炸药水下能量可达到2.1倍TNT当量,并出现最大值.含铝质量分数10%～50%的DNTF基炸药的水下能量随铝含量的增加呈上升趋势,其最大值可达到2.67倍TNT当量.当铅或硼的质量分数低于18%时,含硼DNTF炸药的能量高于含铝炸药.硼铝联用,也可获得较好的能量特性.     

含硼金属炸药水下能量的实验研究

通过水下试验测试了含硼铝、硼镁、硼镁铝合金、硼钛、硼锆等混合金属粉炸药的水下能量,并与相应含铝炸药的水下能量进行了对比.结果发现,以HMX为基金属粉的质量分数20%时,镁粉、镁铝合金与硼粉混合后水下(总能量)比单独使用硼粉时约提高40%;含硼铝质量分数20%的炸药的水下总能量比含铝质量分数20%炸药高约7%;以RDX为基,含硼铝、硼镁、硼镁铝合金质量分数20%炸药的水下总能量比含铝20%的炸药均有提高,其中硼镁达到9%.随着硼铝金属粉含量的增加,水下总能量不断提高,均高于相应含铝炸药,当硼铝金属粉质量分数为35%时达到最高,比含铝35%炸药约高7%,含量40%后开始降低.硼粉与铝粉混合使用,可提高硼粉氧化效率和炸药水下总能量.     

硼粒子表面包覆对富燃料推进剂热分解特性的影响

借助于ＤＴＡ、ＴＧ、ＤＳＣ等热分析手段，研究了硼表面包覆对Ｂ／Ｍｇ／ＡＰ／ＨＴＰＢ富燃料推进剂热分解特性的影响。用于硼粒子表面包覆的材料有ＡＰ、ＫＰ及ＬｉＦ。为便于对比，对含未包覆硼的基础配方也作了相应分析。研究表明，硼包覆有助于提高硼粒子的反应活性，可促进燃料的热分解。从而对提高含硼富燃料推进剂的燃烧性能极为有利。     

含硼固体推进剂燃烧残渣中三氧化二硼和碳含量测定及燃烧机理研究

为了研究含硼富燃料固体推进剂燃烧机理,对3种配方的不同批次含硼富燃料固体推进剂在不同压强的燃速进行了测试,利用化学分析法对其燃烧残渣中B2O3和C含量也进行了测定。结果表明,硼粒子表面的B2O3延缓了硼粒子的进一步燃烧,因此残渣中B2O3含量较低;随着氮气压强增高,残渣中B2O3含量降低,而C含量、B2O3与C总含量升高;随着推进剂配方中镁含量增高,残渣中B2O3含量降低,C含量先升后降,B2O3和C总含量则降低。     

温压药剂的热毁伤研究

运用红外热成像仪分别测量了不同质量的温压药剂和TNT爆炸火球的表面温度.根据实测结果分析了温度场的分布情况,并拟合出温压药剂爆炸火球的直径、持续时间与装药量的关系式.依据炸药的爆炸特性,确定了热毁伤准则,结合Baker火球模型,对温压药剂和TNT爆炸产生的不同程度的热毁伤半径进行了计算.结果表明,温压药剂具有较好的热毁伤效应,用作用区面积评价法可获得温压药剂的TNT当量比为3.89.     

RDX对含硼富燃料推进剂一次燃烧产物组分影响的计算研究

为了研究黑索今(RDX)对含硼富燃料推进剂一次燃烧产物组分的影响,用吉布斯最小自由能法计算了5种推进剂配方的一次燃烧产物组分,并通过测试燃烧产物中的总硼含量对热力学计算结果进行了验证。结果表明,采用最小自由能法计算含硼富燃料推进剂的一次燃烧产物组分,其结果准确、可靠;当含硼富燃料推进剂中RDX含量增加时,一次燃烧产物中B_4C和B_2O_3含量减少、C和BN含量增加,且一次燃烧温度也升高;提高一次燃烧压强可提高硼的氧化率、降低B_4C的生成量,有效提高一次燃烧温度,因此提高一次燃烧压强有助于提高含硼富燃料推进剂的二次燃烧效率。     

铝/乙醇基纳米浆体燃料的着火燃烧特性研究

为了明确纳米铝粉从低浓度到高浓度变化对液体碳氢燃料着火燃烧特性的影响,采用液滴悬挂法研究了不同温度下(700~800℃)乙醇液滴和添加不同浓度(2.5wt%, 10wt%, 15wt%和20wt%)纳米铝粉的铝/乙醇基纳米浆体燃料液滴的着火燃烧特性。利用高速摄影系统捕捉了液滴整个燃烧过程,分析了其液滴寿命。通过热电偶对液滴附近气相温度的测量,获得了其着火性能参数。结果表明,添加纳米铝粉可以改善乙醇液滴的着火性能。不同铝粉浓度改善效果不同,低浓度时效果较好,着火延迟时间显著缩短,点火温度明显降低。随温度升高,乙醇及添加纳米铝粉的铝/乙醇基纳米浆体燃料液滴着火延迟时间及着火温度均明显降低。纳米铝粉(S2)对乙醇(S1)着火延迟时间和液滴寿命的降幅在750℃最大,其降幅分别达42.20%和18.43%。纳米铝粉(S3)着火温度降低,其最大降低幅度也出现在750℃,相对于乙醇(S1)降低幅度达28.57%。一定铝粉浓度范围内,液滴微爆炸程度和微爆炸时长随铝粉浓度升高而增大,但铝粉浓度超过10wt%后趋势变得平稳。     

金属燃料在固体推进剂中的应用进展

综述了硼粉、铝粉、镁粉和合金粉等金属燃烧剂在固体推进剂中的应用状况,展望了其在固体推进剂中的应用前景。认为在固体推进剂中添加一定量的金属燃料来提高推进剂的能量有着很大的发展潜力。     

Investigation of Fireball Temperatures in Confined Thermobaric Explosions

New composite metalized explosives were studied. The explosives consisted of two different types of macroscopic granular multi‐component RDX‐based formulations. In a 0.15 m³ explosion chamber, fireball temperature histories for numerous cylindrical pressed and layered charges made from the composites were determined using optical spectroscopy. For comparison, charges consisting of simple mixtures instead of the composites as well TNT and RDX phlegmatized (RDXph) charges were also studied. The influence of the structure of the macroscopic granular composite, the charge type (pressed charge or layered charge with an RDXph core), oxygen availability (air or argon atmosphere) and aluminum particle size on the fireball temperature and the combustion of the aluminum powder were determined. The measured temperatures were compared with the theoretical ones calculated by assuming different activity of the aluminum fuel.     

硼金属化RDX基炸药的热行为

采用热重(TG-DTG)及高压差示扫描量热(PDSC)技术,考察了含硼金属化RDX基炸药的热行为。研究了不同金属组分对金属化炸药热分解性能的影响,计算获得热分解的动力学参数表观活化能及指前因子。结果表明,RDX分解及其分解产物能"活化"硼粉,使之在高温下更易被氧化或氮化,而RDX对Al粉或Mg粉氧化反应的影响相对较小;B、Al和Mg金属粉的加入导致RDX的热分解反应表观活化能和速率降低,DSC(PDSC)和DTG峰温滞后,DSC的量热值下降。     

Ignition and Combustion of Condensed Systems with Energy Fillers

This paper describes the results of an experimental study of ignition and combustion of condensed systems, containing energy fillers, i.e., powders of aluminum, boron, aluminum borides, and titanium. Compositions on a hydrocarbon or active fuel binder with a combined oxidizer (ammonium perchlorate and/or ammonium nitrate) are considered. Thermodynamic estimates for the ballistic characteristics of the compositions under study are given. It is shown that a unit pulse increases by 3.5% with the replacement of aluminum by boron in the compositions considered. It is experimentally determined that the time delay of ignition of boron-containing compositions decreases in conductive and radiant heat transfer and that the stationary burning rate of boron and aluminum boride containing compositions increases. The efficiency of the impact of energy fillers on the characteristics of condensed systems as a function of the composition of a combined oxidizer is determined.     

基于气固两相反应流的温压炸药能量释放规律数值模拟及实验验证

为研究气体环境、铝粉含量、空间体积对温压炸药能量释放的影响,基于气固两相反应流模型,建立有限差分-物质点耦合算法,对温压炸药密闭容器内爆炸流场演化进行数值模拟及实验验证。结果表明,温压炸药在空气环境中爆炸释放的能量高于氮气中,壁面冲击波峰值压力和空间准静态压力的增幅分别在20%和80%以上,空间准静态压力随空间体积的增大呈先增大后减小的趋势;铝粉含量越高,冲击波在传播过程中衰减得越慢,空间准静态压力越高;铝粉燃烧反应度随空间体积的增加而下降,当比空间体积超过100m³/kg时,反应度下降到90%以下,且铅粉含量越高,其反应程度越低。     

DB/AP系燃烧剂的设计与性能研究

设计了以双基(DB)推进剂、高氯酸铵(AP)为主要组分的燃烧剂,并加入金属可燃剂B、Mg、Al来调整燃烧剂的燃烧性能,采用全自动量热仪、数码摄像机、热电偶和TG-DSC测试了燃烧剂的燃烧热、燃速、火焰温度和热性能.结果表明,金属粉的加入可以提高燃烧剂的燃烧热、燃速和火焰温度,并可以改变其火焰结构;对于长距离、高沸点物质的引燃,3种金属粉中B粉的效果最佳,DB/AP/B的火焰温度可达1 070℃,火焰长度达25cm,其燃烧过程也更稳定,而DB/AP/Mg和DB/AP/Al在燃烧过程中产生大量的火星;AP和金属粉对DB推进剂的热分解没有影响.     

Optical Pyrometry of Fireballs of Metalized Explosives

Fast‐response optical diagnostics (a time‐integrated spectrometer and two separate fast‐response three‐color pyrometers) are used to record the transient visible radiation emitted by a fireball produced when a condensed explosive is detonated. Measurement of the radiant intensity, in several narrow wavelength bands, is used to estimate the temperature of the condensed products within the fireball. For kg‐scale conventional oxygen‐deficient homogeneous TNT and nitromethane explosive charges, the radiant intensity reaches a maximum typically after tens of milliseconds, but the measured fireball temperature remains largely constant for more than 100 ms, at a value of about 2,000 K, consistent with predictions using equilibrium thermodynamics codes. When combustible metal particles (aluminum, magnesium or zirconium) are added to the explosive, reaction of the particles enhances the radiant energy and the fireball temperature is increased. In this case the fireball temperatures are lower than equilibrium predictions, but are consistent with measurements of particle temperature in single particle ignition experiments.     

Combustion heat of the Al/B powder and its application in metallized explosives in underwater explosions

An underwater explosion test is used to determine the detonation properties of metallized explosives containing aluminum and boron powders. An oxygen bomb calorimeter (PARR 6200 calorimeter, Parr Instrument Company, USA) is used to obtain the heat of combustion of the metal mixtures. As the content of boron powders is increased, the heat of combustion of the metal mixtures increases, and the combustion efficiency of boron decreases. The highest value of the combustion heat is 38.2181 MJ/kg, with the boron content of 40%. All metallized explosive compositions (RDX/Al/B/AP) have higher detonation energy (including higher shock wave energy and bubble energy) in water than the TNT charge. The highest total useful energy is 6.821 MJ/kg, with the boron content of 10%. It is 3.4% higher than the total energy of the RDX/Al/AP composition, and it is 2.1 times higher than the TNT equivalent.