LOVA发射药点火燃烧性能

制备了含有两种不同黏结剂的低易损性发射药(即LOVA发射药),并应用点火燃烧模拟装置与密闭爆发器对其点火燃烧性能进行了研究。结果表明,LOVA发射药难点火,但在点火药中添加高氯酸铵后可有效改善LOVA发射药的点火性能。LOVA发射药燃烧具有燃速系数低、燃速压力指数高等特点。     

一种LOVA发射药燃烧残渣现象分析

针对点火模拟装置中某种LOVA发射药燃烧结束留有残渣的现象,将自制样品在常温和常压下进行环境燃烧试验、中止燃烧试验及SEM观察.归纳出残渣产生的原因,分析了LOVA发射药的燃烧规律和燃烧特性.结果表明,配方中RDX组分与含能黏结剂BAMO/AMMO聚合物体系的燃烧不同步性、以及该类发射药氧含量低是造成LOVA发射药燃烧...     

一种低易损固体发射药的等离子体点火及燃烧特性

采用密闭爆发器实验对低易损性(LOVA)发射药等离子体点火和燃烧性能进行了实验研究,通过分析P-t曲线和dP／dt-P／P-曲线的变化规律,探讨了等离子体对该种火药作用机理,以便进一步研究它用于电热化学炮发射试验中的装药结构和增强燃烧的机理。     

发射药初温和热物性参数对点火性能影响的研究

采用点火模拟试验装置，对几种发射药在常，低温情况下的点火性能进行试验，获得了这几种发射药在不同温度下的点火特征曲线及重要参数，得出了这几种发射药在不同温度下的点火性能差异，并结合火理论作数值计算，分析了发射药初温对点火性能影响的内在原因，为进一步研究低温下发射药膛内的点火特性及燃烧过程提供依据。     

一种新型评价发射药点火性能的试验方法

为了科学评价发射药的点火性能,建立了一种以特征点火药量为评价指标的新型试验方法。在密闭装置中调整点火药量进行点火试验,得到最低点燃点火药量,作为评价发射药的点火性能。该方法可以区分不同发射药的点火性能,对比不同点火药的点火能力。     

适用于硝胺发射药的点火药

采用NC,NH4ClO4,BP常用点火材料组成不同的点火剂配方，考察其对含RDX的硝胺火药的点火能力，以点燃性能较好的硝化棉，单基药（SL）作基准，通过点火模拟对比试验，获得了可提高硝胺发射药点火效能的新型点火药配方，点火剂E（含NC23．1％，38．5％，NH4ClO438.5%）在低温（－40℃）条件下点燃硝胺药的点火延迟时间（tig）与制式单基药tig相当。     

液体发射药在模拟火炮使用条件下压缩点火特性研究

采用液体发射药绝热压缩感度测试装置，试验研究两种液体发射药ＨＹ９１１和鱼推－Ⅱ含气泡与不含气泡两种状态下的绝压缩点火特征，阐述了液体发射药在火炮上安全使用的可能性。     

ETPE发射药等离子体点火的燃烧特性

为解决ETPE发射药点火延迟时间长及难点火的问题,用高功率脉冲电源通过等离子体发生器产生电弧等离子体点燃ETPE发射药,并研究了ETPE发射药在等离子体作用条件下的点火燃烧特性.结果表明,与常规点火方式相比,等离子体作用使ETPE发射药的燃速显著增强,点火延迟期缩短,点火的一致性改变.分析认为,等离子体高温高速射流的强作用使得RDX颗粒快速越过吸热熔融过程达到分解放热阶段,所以ETPE发射药点火延迟期缩短以及燃烧初期燃速提高.     

带延迟点火部件的发射药点火性能试验研究

为了更好地研究发射药的点火性能,在基于密闭爆发器原理的点火性能测试装置基础上增加了一个延迟点火部件,构建了一个新型点火性能模拟试验装置,根据该装置建立了简单的火药分层点火过程模型,模拟并对比了高能太根-18/1、双芳-3-18/1及NR11-18/1三种发射药的点火性能。结果表明,NR11-18/1发射药较易点火,双芳-3-18/1发射药最难点火,点火时间分别为19和45ms。增加延迟点火部件后,可将点火药的燃烧和发射药的燃烧阶段有效区分,不仅有利于对比点火性能差异较小的发射药之间的区别,还有助于分析发射药低压段的燃烧速度。随着延迟点火部件长度的增加,点火时间也增长。     

双基发射药热碎片传导点火实验及影响因素

为研究发射药在高温碎片作用下的点火和燃烧行为,选热钢材圆柱体作模拟碎片,模拟高温碎片作用于发射药的点火和燃烧过程,建立了用于发射药热碎片传导点火的实验装置,确定了在热碎片作用下易损性的表征参数,研究了双基发射药在热碎片作用下的点火和燃烧行为。结果表明,碎片温度、碎片尺寸、药型尺寸及样品环境条件是影响同一配方发射药热碎片传导点火的主要因素。     

固体含能工质等离子体单药粒点火特性分析

作为固体工质电热化学（SPETC）炮等离子体点火特性的基础性研究,本文利用等离子体切割机提供的等离子体源,对单基、多基火药的等离子体点火特性进行了实验研究,得出了不同类型火药在不同点火强度条件下的点火特性,为后续的等离子体内弹道环境点火特性研究提供了基础。     

Flash Tube Lacquer Seal Dynamic Rupture Strength in 30‐mm Ammunition

The M788, M789, and M799 30‐mm ammunition use a flash tube to augment the ignition stimulus of the primer and to provide an ignition source for the propellant bed in each round. The flash tube must be fast acting, provide abundant hot gases/particles, and increase the pressure in the propellant bed sufficiently so that the initial burn rate of the propellant in the bed is high enough to propel the projectile to the muzzle within the few milliseconds that constitute the action time of the M230 cannon. This investigation studied the dynamic rupture pressure of the lacquer seal on the flash tube. The rupture pressure of the seal was found to be a function of the pressurization rate in the flash tube. At the largest rupture pressure of this study (78 MPa), significant gas generation would be achieved before the flash tube vented into the main propellant bed. Gas flow at these pressures is expected to play a significant role in ignition of the main propellant charge and rapid functioning of the round.     

Experimental Investigation on Laser Ignition and Combustion Characteristics of NEPE Propellant

The ignition and combustion property of solid propellant is the main content in internal ballistic research, which has a great significance for propulsion application and combustion mechanism. In this study, the detailed gas‐phase reaction mechanism of Nitrate Ester Plasticized Polyether Propellant (NEPE) was developed. It is helpful to understand the intricate processes of solid‐propellant combustion. The factors which may have influences on ignition delay time and temperature distribution of propellant surface was analyzed by laser ignition experiment. Using high‐speed camera and an infrared thermometer, the ignition and combustion process and the surface temperature distribution of NEPE propellant under laser irradiation were measured. Laser heat flux, ambient pressure and initial temperature of NEPE propellant have an influence on the ignition delay time and the surface temperature. Results show that the ignition delay time decreases with the increase of laser heat flux, ambient pressure and initial temperature of NEPE propellant. At the same time, with the increase of laser heat flux, the influences of ambient pressure and initial temperature on the ignition delay time decrease. Besides, laser irradiation, ambient pressure and initial temperature have significant influences on the surface temperature distribution of the propellant.     

Flame Spreading in a LOVA Charge: An Experimental Study

LOVA propellants due to their low sensitivity are difficult to ignite. ‘Non-ideal’ ignition can result in loss of accuracy, misfire, hangfire or catastrophic failure of the gun. The flame spreading event can be used to evaluate the ignition process. An experimental technique has been developed to aid in the investigation of flame spreading in gun charges. Fibre optic sensors as a direct measurement method were used to record radial and axial flame spreading. Experiments were conducted for three different igniter designs. Significant differences in the flame spread history for the three igniters were found and the technique proved to be suitable for optimization of ignition systems. Results of the experimental study could be used to validate interior ballistic model predictions.     

减小高装填密度发射装药膛内压力波的实验研究

研究了两种能降低某大口径火炮高装填密度发射装药的膛内压力波的点传方案。第一种点传火方案是在制式点传火结构基础上增加横向传火具,增加点火药包;第二种点传火方案是改变制式传火结构为低爆速传火结构,同时增加横向传火具。高装填密度发射装药射击试验表明,这两种点传火方案均能满足点传火要求。第一种点传火方案较制式可燃中心传火管能实现迅速全面的点火,但出现了压力波增大的现象。而第二种点传火方案较第一种点传火方案的传火速度快,能迅速建立点火压力,发射药床的着火延迟时间小,最重要的是能抑制膛内有害压力波。压力波的频谱分析表明在高装填密度装药中,采用第二种点传火方案能削弱和抑制压力波的高频振荡成分,改善其振动特性。     

Laser-induced ignition of solid propellants for gas generators

An experimental study was conducted to evaluate the ignitibility of a family of potential gas-generator solid propellants under different CO₂ laser heat fluxes and chamber operating conditions. Six types of solid propellant were tested: one baseline and five variations. The ingredients of the baseline propellant were ammonium nitrate, guanidine nitrate, potassium nitrate, and polyvinyl alcohol. The other five propellant variations were obtained by adding different amounts of carbon black, ammonium perchlorate, RDX, and triamino guanidine nitrate to the baseline formulation. The propellants were tested in a high-pressure windowed strand burner, which was pressurized with either air or argon purge gases. Propellant ignition was accomplished by a 50-W CO₂ laser. The ignition delay times of the propellants were measured at pressures of 1 and 69 atm using high-speed video cameras. In this paper, the test results and comparison of the ignition and combustion characteristics of these propellants were presented.     

高能低易损性发射药试验研究

通过对低易损性发射药用粘结剂、增塑剂、燃烧改良剂的选择和配方设计及理论计算,并结合试验研究,对所设计配方的能量、燃烧及力学性能进行了试验论证,基本确定了以RDX为含能填料、惰性和含能复合粘结剂、复合增塑剂及燃烧改良剂和力学性能改善剂所组成的低易损性发射药配方类型;证明了采用溶剂法挤压成型工艺技术路线的可行性.     

Response of TEGDN Propellants to Plasma Ignition with the Same Magnitude of Ignition Energy as Conventional Igniters in an Interrupted Burning Simulator

In order to consider the potential influence of ignition energy factors on the response of double base propellants plasticized with triethyleneglycol dinitrate (TEGDN propellants), the influence of different ignition methods at the same magnitude of ignition energy level on the response of TEGDN propellants was investigated in an interrupted burning simulator. Compared to conventional ignition methods, plasma ignition exhibits a significantly shorter ignition delay and lower ignition energy. There are stronger ablation and impact interactions of plasma flow with the surface of propellants. For TEGDN propellants coated with titanium dioxide, a greater amount of melted white layer is deposited on the surface of propellants. The content of copper on the surface of recovered plasma‐ignited samples observed by X‐ray Fluorescence (XRF) spectroscopy is much larger than that on the surface of recovered conventionally ignited samples, indicating more deposition of copper wire discharge on the surface of the samples. The test results will benefit the design of plasma generator and electrical parameters of pulse power to satisfy certain propellant compositions.