组分对高能HTPB推进剂燃烧性能和力学性能的影响

通过调整氧化剂AP粒径与含量、键合剂及R值，研究了固体质量分数为90％的HTPB推进剂的燃烧性能和力学性能。结果表明，在HTPB推进剂能量性能得到提高的同时，推进剂的燃烧性能和力学性能也得到了较好的保证。高固体含量下HTPB推进剂的燃烧和力学性能随配方调节呈现出较为明显的规律。推进剂的燃烧性能稳定，燃速和压力指数可调，压力指数控制在0．30～0．40；分别测定了高温（60℃）、常温（20℃）和低温（-40℃）力学性能，高温、低温和常温下的拉伸强度一般均大于1．0MPa，低温延伸率最高可达74．7％。     

铝基合金燃料在HTPB推进剂中的应用

通过改变铝基合金燃料类型制备低铝含量推进剂,在此基础上进行铝基合金的粒度、形貌和推进剂的爆热、燃速测试,研究了不同铝基合金燃料对端羟基聚丁二烯(HTPB)推进剂工艺性能、燃烧性能及安全性能的影响。推进剂组分相同时,黏度数据表明,铝基合金的不规则形貌是引起推进剂工艺恶化的主要因素,粒度差异会使工艺性能有所不同;燃烧性能测试和爆热测试结果表明,添加铝基合金AN(铝-镍合金燃料)和AT(铝-钛合金燃料)后,与含球形铝粉推进剂相比,推进剂密度增加,燃速压强指数降低,爆热水平相当,燃烧性能得到了改善;添加铝基合金燃料后造成推进剂的摩擦感度上升。     

铝含量和含氟有机化合物对丁羟推进剂燃烧性能的影响

为进一步提高HTPB推进剂的能量并抑制铝粉在燃烧过程中的团聚,制备了铝粉质量分数为16%~22%的端羟基聚丁二烯(HTPB)推进剂,并分别加入含氟有机化合物(OF)作为铝燃烧促进剂,研究了铝含量和OF对HTPB推进剂燃烧性能的影响;使用氧弹量热仪测定了推进剂在氩气氛围下(3 MPa)的爆热;收集在3 MPa下推进剂燃烧的凝聚相产物,采用激光粒度仪、X射线光电子能谱仪(XPS)及X射线衍射仪(XRD)等分别对其进行粒度分布、元素和物相分析;通过线扫描摄像机和高压燃烧室系统测定推进剂的燃速;利用高速摄影系统观察推进剂燃面上熔铝粒子的团聚过程。结果表明,HTPB推进剂在铝粉质量分数为20%时实测爆热最大,含氟有机物OF的引入使得爆热有所下降;随着HTPB推进剂中铝含量的提高,燃面上熔铝粒子的团聚愈加严重,凝聚相燃烧产物的尺寸和残留铝含量均逐渐增加;加入含氟有机物OF能够促使-Al2O3和AlF3的生成,有效抑制铝颗粒在燃烧过程中的团聚,使凝聚相燃烧产物的尺寸和残留铝含量显著降低,当铝粉质量分数为20%时,OF的加入使得残留铝的生成率降低了50%;较低的铝含量和OF的添加有利于HTPB推进剂燃速的提高。     

低铝含量HTPB固体推进剂的燃烧特性

为研究低铝含量推进剂的燃烧特性,以铝粉质量分数5%的低铝含量HTPB推进剂为对象,以铝粉质量分数12%～18%的HTPB推进剂为参比,通过水下声发射、BSFΦ75及BSFΦ165标准试验发动机等测试方法研究了低铝含量推进剂的燃烧性能和能量性能。结果表明,同一固含量条件下,低铝含量推进剂燃速较高,压强指数没有明显变化;铝粉粒度越细,低铝含量推进剂燃速和燃速压强指数越大;经BSFΦ75发动机内弹道p(压力)—t(时间)曲线验证,8～10MPa内低铝含量推进剂燃烧稳定;经BSFΦ165发动机试车验证,7MPa下,低燃速低铝含量推进剂实际比冲2387N·s/kg,比冲效率达到97.3%,高燃速低铝含量推进剂实际比冲2465N·s/kg,比冲效率达到98.6%。低铝含量推进剂燃烧效率高,相近燃速下低铝含量推进剂与常规铝含量推进剂能量在同一水平。     

含铜催化剂对RDX/AP/HTPB推进剂燃烧特性的影响

采用热分析方法，研究了五种新型含铜催化剂对ＡＰ、ＡＰ／ＲＤＸ热分解特性的影响，从中筛选出两种催化效果比较好的催化剂。进一步研究了它们对ＡＰ／ＲＤＸ／ＨＴＰＢ推进剂燃速及燃速压强指数的影响。结果表明：这两种催化剂对提高燃速，降低压强指数有明显效果，经适当组合，可进一步提高燃速，降低压强指数。     

化学共混对HTPB推进剂性能的影响

寻找合适的混合方式将端羟基四氢呋喃环氧乙烷共聚醚(PET)共混于端羟基聚丁二烯(HTPB)推进剂中,研究PET黏合剂和BDNPA/F(双(2,2–二硝基丙醇)缩乙醛/双(2,2–二硝基丙醇)缩甲醛)增塑剂对HTPB推进剂力学性能和燃烧性能的影响。结果表明:采用二步聚合法可将PET加入HTPB推进剂中,推进剂具有较好的工艺性能和力学性能;PET的加入能明显降低推进剂的燃速和压强指数;同时,极性黏合剂的加入有助于引入含能增塑剂BDNPA/F。     

HTPB/Al/AP/RDX推进剂初始燃烧的分子模拟

针对一种四组元HTPB推进剂(HTPB/Al/AP/RDX)关键组分,基于第一性原理计算的数据集,使用深度神经网络模型开发了一个机器学习势函数;基于新开发的势函数,建立了四组元HTPB推进剂燃面模型,并进行了大规模的分子动力学模拟计算,对推进剂燃烧时的微观结构、温度、反应组分的时空演化进行了系统统计分析。结果表明,新开发的势函数能够准确描述推进剂组分单质及两两之间界面的能量和受力特性,是一个高精度、高效率的机器学习势函数;燃面模型实现了对推进剂燃烧过程中的AP、RDX、HTPB热解过程精准模拟,阐明了扩散火焰的形成机理以及铝粉从燃面剥离等微观过程,揭示了其中的各组分界面相互作用机制。表明分子动力学模拟能够在原子尺度上实现时间分辨的三维重建,进而获得推进剂燃烧的微观机理,可为固体推进剂的理论研究提供了新的工具。     

含能复合催化剂对微烟推进剂燃烧性能的影响

为研究含能催化剂对微烟推进剂燃烧性能的影响,制备了多种含复合含能催化剂的RDX-CMDB推进剂,利用靶线法测定了推进剂在不同压力下的燃速,并对测试结果进行了线性回归.结果表明,在研究的含能催化剂中,2HDNPPb/2HDNPCu和4HDNPPb/2HDNPCu复合催化剂对推进剂有更好的催化效率和降低压力指数的能力.将含能复合催化剂与单一含能催化剂的催化作用进行比较得出,当催化剂加入量一定时,羟基吡啶铅盐、铜盐复合使用比单一的铅盐或铜盐有更好的催化效果.     

组分对高能HTPB推进剂燃烧性能和力学性能的影响

通过调整氧化剂AP粒径与含量、键合剂及R值,研究了固体质量分数为90%的HTPB推进剂的燃烧性能和力学性能.结果表明,在HTPB推进剂能量性能得到提高的同时,推进剂的燃烧性能和力学性能也得到了较好的保证.高固体含量下HTPB推进剂的燃烧和力学性能随配方调节呈现出较为明显的规律.推进剂的燃烧性能稳定,燃速和压力指数可调,压力指数控制在0.30～0.40;分别测定了高温(60 ℃)、常温(20 ℃)和低温(-40 ℃)力学性能,高温、低温和常温下的拉伸强度一般均大于1.0 MPa,低温延伸率最高可达74.7%.     

高效含能燃烧催化剂对双基推进剂燃烧性能的影响

研究了含能有机铅、铜盐即3-硝基-1,2,4-三唑-5酮(NTO)和4-硝基咪唑铅、铜盐及其复配体系对双基推进剂燃烧性能和燃烧残渣率的影响.结果表明,NTO和4-硝基咪唑铅、铜盐及其复配体系均可明显提高双基推进剂的燃速,降低推进剂的压强指数;NTO和4-硝基咪唑铅、铜盐与炭黑形成的铅/铜/炭燃烧催化剂复配体系使双基推进...     

Effect of Organic Fluoride on Combustion Agglomerates of Aluminized HTPB Solid Propellant

Hydroxyl‐terminated polybutadiene (HTPB) based propellants containing fixed aluminum content (18 wt %) and different amounts of organic fluoride (OF) additive were studied. Explosion heat of propellant samples and particle size distribution of the solid combustion products were experimentally measured to generally assess the effect of the organic fluoride compounds on propellants. Heats of explosion decreased approximately by 9.5 %, from 7209 (±259) to 6525 (±146) kJ kg⁻¹, with the increase in OF content from 0 % to 6 %, and the volume fraction of particles size above 10 μm was sharply decreased. In addition, scanning electron microscope images showed the solid combustion products to be well separated, the titration analysis results also gave the amount of unburned metallic aluminum decreased. These results indicated that OF as an additive would be helpful to reduce agglomeration in the combustion products of aluminized HTPB propellants. Furthermore, a mechanism for suppression of agglomerate size can be postulated based on the X‐ray diffraction analysis data that addition of OF promotes increased content of γ‐Al₂O₃ (aluminum oxide) in the solid combustion products.     

适应高压强的HTPB推进剂的燃烧性能

为改善高压强下HTPB推进剂的燃烧特性,研究了碳酸盐复合调节剂、二茂铁衍生物G、高氮化合物M、纳米铝粉和纳米金属氧化物对HTPB推进剂燃烧性能的影响.结果表明,碳酸盐复合调节剂能够降低推进剂的燃速和压强指数;二茂铁衍生物G能够提高推进剂的燃速,同时将推进剂在8.60～17.12MPa下的压强指数降至0.27;高氮化合物也可降低推进剂的燃速和压强指数;将高氮化合物M与二茂铁衍生物G配合使用可将推进剂在8.63～16.48MPa下的压强指数降至0.24; 纳米铝粉和包覆的纳米金属氧化物可明显降低推进剂的燃速压强指数.     

纳米催化剂对双基系推进剂燃烧性能的影响

研究了10种不同纳米催化剂对双基或RDX—CMDB推进剂燃烧性能的影响,发现经表面处理的纳米复合物(n—TPCC)是一种非常有效的纳米催化剂,它使得双基推进剂在6～10MPa呈现麦撤燃烧特征,8～IOMPa的压力指数为-0．867;改进n—TPCC加入方法后,可显著提高n—TPCC在低压下的催化效率;在RDX—CMDB推进剂中,n—TPCC与碳黑复合后,其催化效率进一步提高,且使推进剂在12-22MPa出现了一个宽压力范围的平台区,燃速压力指数小于0．3。     

两种新型键合剂改善 AP/HTPB 推进剂力学性能的作用效果

通过单轴拉伸试验，研究了两种新型键合剂改善ＡＰ／ＨＴＰＢ复合固体推进剂力学性能的作用效果，及其对推进剂工艺性能的影响。研究表明，这两种新型键合剂能够明显地改善推进剂的力学性能，且推进剂的工艺性能良好。     

Study on Unsteady Combustion Behaviors of AP/HTPB Base‐Bleed Propellants under Transient Depressurization Conditions

As the base‐bleed projectile flies out of the muzzle, the environmental pressure in the base‐bleed combustion chamber suddenly decreases and AP/HTPB base‐bleed propellant suffers intense unsteady combustion. To further study the unsteady combustion characteristics of base‐bleed propellants, a semi‐closed bomb as was designed experimental device and transient depressurization conditions of the muzzle were simulated. Measurements of the transient combustion characteristics of the base‐bleed propellant under high depressurization rate were carried out by using a high speed digital camera system. In the experiments, the combustion chamber pressure of the semi‐closed bomb was controlled from 20 to 90 MPa and the depressurization rate was controlled from 400 to1.12×10⁴ MPa s⁻¹. The experimental results indicate that, the out‐of‐phase blowing effect is intense under rapid depressurization condition, leading to the reaction layer thickened. The thermal feedback to the solid surface decreases and thus the combustion reaction of gas phase is so difficult to maintain that it begins to extinguish. However, the thermal decomposition of the solid phase is still continuing and a yellow fog can be observed above the combustion chamber nozzle. Depending on the maximum pressure in the combustion chamber and depressurization rate, the transient combustion behavior of AP/HTPB base‐bleed propellant displays three patterns, i.e., automatic reignition, oscillating combustion (a critical type) and permanent extinguishment. Three unsteady combustion behaviors are preliminarily analyzed based on the thermal feedback. If the initial pressure in the combustion chamber before depressurization is larger or the depressurization rate is smaller, the base‐bleed propellant tends to automatically reignite earlier and the combustion process is more stable.     

Influence of Particle Size on the Combustion of CL‐20/HTPB Propellants

The effect of nitramine particle size on the combustion behavior of inert binder based propellants has been extensively studied for RDX and HMX, but not CL‐20. Although materials such as RDX and HMX are useful for particular combustion applications, CL‐20 has a greater potential to improve the oxygen balance and energy density of a propellant. The current work investigates the effect of CL‐20 particle size on the combustion of CL‐20/HTPB propellants down to submicrometer sizes. An influence of particle size on the burning rate and combustion mechanism is reported. The 30 micrometer formulation burning rate data showed evidence of convective burning specifically at higher pressures, but the pressure dependence was comparable to neat CL‐20 at pressures below 8 MPa. A change in the combustion mechanism of the submicrometer formulation as a function of pressure was determined to be a result of the interaction of the propellant flame and the combustion residue. Data suggested that at low pressures diffusion in terms of active cooling was dominant for the submicrometer formulation. Higher pressure data for both the submicrometer and 3 micrometer formulations suggest the degree of active cooling is decreased as the burning rate pressure exponent is near 0.5 for both propellants. The indirect evidence for the presence of a melt layer for CL‐20 propellants is discussed.     

有机铋铜复盐对DNTF/HMX-CMDB推进剂燃烧性能的影响

研究了有机铋铜复盐(Gal-BiCu)与炭黑、不同芳香族铜盐(Cu1和Cu2)及金属燃烧功能助剂(NB)复配对DNTF/HMX-CMDB推进剂燃烧性能的影响。分析了Gal-BiCu与其他催化剂复配后影响DNTF/HMX-CMDB推进剂燃烧行为的原因。结果表明,Gal-BiCu能有效调节DNTF/HMX-CMDB推进剂的燃烧性能,提高推进剂燃速,显著降低压强指数;当Gal-BiCu与炭黑、Cu1、NB复合时,催化性能更佳;NB质量分数为0.5%时,推进剂在8~20MPa较宽区间内出现平台燃烧,压强指数n≤0.2;8~15MPa区间内压强指数降至0.11。