低燃速低燃温双基推进剂燃烧性能的调节

为调节低燃速燃温双基推进剂的燃烧性能(燃速及压强指数)，探索铅、铜盐和碳黑等燃烧催化剂在该类推进剂中的催化效果，从理论燃温在900～1700K的低燃速双基推进剂中选出4种作为基础配方，分别加入不同种类的铅盐、铜盐及碳黑等燃烧催化剂，改变催化剂的加入量及搭配关系，进行了一系列试验研究。同时还研究了辅助增塑剂对推进剂燃烧性能的影响。结果表明，常规的铅、铜盐和碳黑等催化剂在低燃速低燃温推进剂中仍能发挥催化作用，作用效果与催化剂的品种及加入量相关，特别是使用复合催化剂时，对燃烧性能的调节更为有效。不同品种的辅助增塑剂对燃烧性能也有影响。     

ACP对无烟改性双基推进剂能量和燃烧性能的影响

含ACP的无烟改性双基推进剂能量特性理论计算表明,ACP对推进剂的能量影响较小。研究了不同工艺对含ACP无烟改性双基推进剂燃烧性能的影响。实验结果表明,ACP对压伸工艺制备的推进剂燃速没有显著提高,但能大幅度地提高浇铸无烟改性双基推进剂的燃速。分析了ACP提高无烟改性双基推进剂燃速的作用机理,认为ACP可增加燃烧表面积和热量向燃烧表面积的反馈,使推进剂的燃速大增。     

2,4-二羟基苯甲酸铋对双基推进剂燃烧的催化作用

为了考察2,4-二羟基苯甲酸铋对双基推进剂燃烧的催化效果以及探索其催化作用机理,用螺压工艺制备了含2,4-二羟基苯甲酸铋的推进剂样品,研究了2,4-二羟基苯甲酸铋对双基推进剂燃烧的催化性能。结果表明,2,4-二羟基苯甲酸铋对双基系推进剂的燃烧具有良好的催化作用,能显著提高推进剂的燃速,并大大降低压力指数,与少量碳黑复合后,对提高推进剂的燃速效果更明显,铋盐、铜盐与碳黑三元复合后,催化效果更优。用快速热裂解固相原位池／傅里叶变换红外光谱（RSFT-IR）联用装置研究了2,4-二羟基苯甲酸铋的热分解机理,发现2,4-二羟基苯甲酸铋在催化推进剂燃烧过程中的活性组分为Bi2O3。     

一种非铅催化硝胺改性双基低燃速低燃温推进剂

为降低双基低燃速低燃温推进剂的燃速、燃温,将含能添加剂PQ加入含HMX的CMDB推进剂中。研究了含能添加剂PQ与HMX复配后部分取代配方中的NC和NG对燃速、燃温的影响,并采用常规的Pb—Cu盐复合催化剂和非铅催化剂体系对该配方体系的燃烧性能进行了调节。结果表明,加入适量的复合含能添加剂能有效降低推进剂的燃速和燃温,可使推进剂理论燃温低于1200K,燃速低于2．5mm／s（10MPa,20℃）;与常规Pb—Cu盐催化剂相比,非铅催化剂的催化效率更高,配方的燃烧性能更好,压强指数可低至0．16（3～7MPa）,获得平台燃烧。含能添加剂PQ降低燃速、燃温的原因是加入PQ后,推进剂的能量水平下降以及PQ在分解时的熔化吸热降低了化学反应速率。     

CuO/CNTs的制备及其对双基推进剂燃烧的催化作用

以醋酸铜和碳纳米管为原料,在常压和100℃下,用溶胶浸渍法制备出CuO/CNTs复合纳米催化剂,采用XRD、TEM等对CuO/CNTs进行了表征,并考察了其对双基推进剂燃烧的催化作用。结果表明,纳米CuO以8～10nm的椭球形粒子和长度50nm、宽度5nm的棒状粒子两种形态附着在碳纳米管表面。CuO/CNTs复合纳米催化剂可显著改善双基推进剂的燃烧性能,使其燃速大幅提高,压强指数降低。在6MPa、质量分数为2.5%时,该催化剂使推进剂的燃速从5.20mm/s提高到11.77mm/s,提高了115%;在16～22MPa出现平台燃烧,在该压强范围内的压强指数从0.617降低至0.238。     

新型致密型多孔燃烧固体推进剂

阐述了过去致密型多孔燃烧高燃速、超高燃速固体推进剂（简称致密型多孔燃烧固体推进剂）的设想及随后发现的国内外与之类似的有关实验现象。分析了这种推进剂能提高燃速的机理。指出致密型多孔燃烧固体推进剂具有常规和多孔推进剂的几乎所有优点，是一种具有强生命力的新型推进剂。     

基于一维气相稳态反应流的燃速预估软件研究

在一维气相稳态反应流模型的基础上,总结了适用于双基推进剂、改性双基推进剂、复合固体推进剂燃速预估的修正因子,拓宽了燃烧理论模型的适用范围.采用Visual C++和Microsoft Access为开发工具,完成了基于组分化学键结构参数的固体推进剂燃速预估软件(SPRS)编制.该软件基于Windows XP系统,界面友好,使用方便,具有数据更新和信息查询功能.用户不仅能根据推进剂的化学组成(配方)和给定压强计算燃速、压力指数等参数,还可根据给定的燃速和压力指数等调整推进剂配方组成,对缩短固体推进剂研制周期和节约研制成本具有重要意义.     

提高复合固体推进剂燃速催化剂催化效率的途径

本文从燃速催化剂的浓度,催化界面,催化剂间的协同效应,以及对现有燃速催化剂进行改性等几个方面综合阐述了提高过氯酸铵复合固体推进剂燃速催化剂催化效率的途径,并用Summerfield燃烧理论作了说明。一、引言固体推进剂的燃烧速度是表征固体推进剂燃烧特征的一个重要参数。在实际应用中,随着发动机的用途不同,对固体推进剂的燃速高低要求也不一致。例如,助推器要求高燃速的     

纳米催化剂对无烟改性双基推进剂燃烧性能的影响

用均匀设计和多元回归分析方法研究了纳米含能有机铅盐n-ONPP、纳米有机铜盐n-PAC和炭黑复配对无烟改性双基推进剂燃烧性能的影响,并建立了多元回归数学分析模型.结果表明,n-ONPP和n-PAC复配或n-ONPP和炭黑的复配,对提高无烟改性双基推进剂2～6MPa的燃速效果显著,而对提高该推进剂在6～22MPa的燃速效果不明显.但一定量且比例适当的n-ONPP、n-PAC和炭黑复配,能显著提高无烟改性双基推进剂在中低压下的燃速,且在中高压段使推进剂出现平台燃烧,但平台燃烧的压强范围随着催化剂比例的不同而不同.理论分析表明,在2～4MPa,对无烟改性双基推进剂燃速起决定作用的是n-PAC和炭黑;n-ONPP、n-PAC和炭黑三者之间的相互作用对燃速也有一定的作用.在6MPa以上,n-ONPP和n-PAC对燃速起决定作用,炭黑起辅助作用.     

铜盐和碳黑对微烟NEPE推进剂燃烧性能的影响

通过测定不同压力下推进剂的燃烧性能及熄火表面元素分析,研究了两种铜盐（AD和BC）和3种碳黑对微烟NEPE推进剂燃烧性能的影响.结果表明,适量AD可改善推进剂的燃烧性能,使推进剂在3～20 MPa压力范围内的压强指数降至0.45以下;AD在12～18 MPa压力范围内比等量BC对微烟NEPE推进剂燃烧性能的催化作用弱,这可能与AD所含铜元素在燃面的富集程度小于BC有关.3种碳黑均能改变微烟NEPE推进剂在3～18 MPa压力范围内的燃速.增加乙炔碳黑含量可使推进剂在3～20 MPa压力范围内的燃速提高,压力指数降低.     

含N,N-二硝基哌嗪无烟改性双基推进剂的燃烧性能

以CMDB推进剂为基础,用N,N-二硝基哌嗪(DNP)替代推进剂中的RDX,研究了DNP含量、燃烧稳定剂(CaCO3、TiO2、MgO及Al2O3)、燃烧催化剂(铅盐、铅盐/铜盐、铅盐/铜盐/炭黑)对DNP-CMDB推进剂燃烧性能的影响。结果表明,DNP可明显降低无烟CMDB推进剂的燃速,当DNP完全替代RDX时,在18MPa压强下推进剂的燃速降低约68%;铅盐/铜盐/炭黑燃烧催化剂复配体系能够有效降低DNP-CMDB推进剂的燃速压强指数,使其出现平台燃烧效应。     

炭黑粒度对CMDB推进剂燃烧性能的影响

用燃速测试、扫描电子显微镜(SEM)和光电子能谱仪(EDS)研究了炭黑粒度对复合改性双基(CMDB)推进剂燃烧性能和熄火表面的影响.结果表明,将炭黑与铅、铜盐催化剂复配使用能够大幅度提高CMDB推进剂的燃速并降低压强指数,且炭黑粒度越小效果越显著,这可能与炭黑对铅、铜盐凝聚的阻滞作用有关.     

Ballistic Modification of Nitramine Propellants with Special Reference to NG‐PE‐PCP‐Based High Energy Propellants

The burning rate pressure relationship is one of the important criteria in the selection of the propellant for particular applications. The pressure exponent (η) plays a significant role in the internal ballistics of rocket motors. Nitramines are known to produce lower burning rates and higher pressure exponent (η) values. Studies on the burning rate and combustion behavior of advanced high‐energy NG/PE‐PCP/AP/Al‐ and NG/PE‐PCP/HMX/AP/Al‐based solid rocket propellants processed by a conventional slurry cast route were carried out. The objective of present study was to understand the effectiveness of various ballistic modifiers viz. iron oxide, copper chromite, lead/copper oxides, and lead salts in combination with carbon black as a catalyst on the burning rate and pressure exponent of these high‐energy propellants. A 7–9 % increase in the burning rates and almost no effect in pressure exponent values of propellant compositions without nitramine were observed. However, in case of nitramine‐based propellants as compared to propellant compositions without nitramines, slight increases of the burning rates were observed. By incorporation of ballistic modifiers, the pressure exponents can be lowered. The changes in the calorimetric values of the formulations by addition of the catalysts were also studied.     

Burning Rate – Pressure Relationship of NG‐PE‐PCP‐based High Energy Propellants

Nitramines are known to produce lower burning rates and higher pressure exponent (η) values. Studies on the burning rate and combustion behavior of advanced high‐energy NG/PE‐PCP/HMX/AP/Al based solid propellant processed by slurry cast route were carried out using varying percentages of HMX and AP. It was observed that propellant compositions containing only AP and Al loaded (total solids 75 %) in NG plasticized PE‐PCP binder produce comparatively lower pressure exponent (η) values similar to AP‐Al filled HTPB based composite propellants. However, energetic propellants containing high level of nitramine (40–60 %) produce high pressure exponent (0.8–0.9) values in the same pressure range. Incorporation of fine particle size AP (ca. 6 μm) and change in its concentration in the propellant composition reduces η value marginally and influences the burning rate. However, such compositions have higher friction sensitivity.     

Correlation of parameters in the burning rate law and its influence on intraballistic characteristics of a rocket motor

Experimental data demonstrating the correlation of parameters in the power-law dependence of the burning rate of composite solid propellants on pressure are reported. The reasons for changes in the burning rate due to changes in propellant mixing conditions are discussed. The deviation of the pressure in the combustor of a solid-propellant rocket motor is analyzed with due allowance for the correlation of parameters in the burning rate law. It is shown that the relative deviation of the burning rate depends on pressure at which propellant combustion occurs. Moreover, for each propellant, there exists a pressure level at which the burning rate deviation is theoretically equal to zero, regardless of the differences in propellant compositions and properties.     

化学结构对平台推进剂催化燃烧性能影响的理论分析

利用建立的以准一维气相反应流为基础的推进剂稳态燃烧模型,计算了推进剂配方组成对催化燃烧性能的影响,从化学结构的角度分析了平台燃烧的影响因素。由此解释了平台燃烧全过程的化学本质和推进剂燃速压强指数的化学本质,提出了平台推进剂配方和燃速优化设计的原则,为燃速和燃速压强指数的调节提供了理论依据,其结论与国内外实践结果相一致。     

Combustion Effects of Nitrofulleropyrrolidine on RDX‐CMDB Propellants

The effect of N‐methyl‐2‐(3‐nitrophenyl)pyrrolidino[3′,4′:1,2]fullerene (mNPF) on the decomposition characteristics of hexogen (RDX) was investigated using differential scanning calorimetry (DSC). The results show that mNPF can accelerate the decomposition of RDX, the peak temperature (T_p) of the exothermal decomposition is reduced by 6.4 K, and the corresponding apparent activation energy (E_a) is decreased by 8.7 kJ mol⁻¹. N‐methyl‐2‐(3‐nitrophenyl)pyrrolidino[3′,4′:1,2]fullerene (mNPF), carbon black (CB), and C₆₀ were used as combustion catalysts to improve the combustion performance of a composite modified double‐base propellant containing RDX (RDX‐CMDB). The burning rate experimental results show that mNPF has a stronger catalytic effect than C₆₀ and CB. The magnitude of the effect of the three carbon substances on the enhancement of the burning rate is as follows: mNPF>C₆₀>CB. The catalytic effects of different contents of mNPF on the burning rates of RDX‐CMDB propellants were also studied, and the results show that the burning rates of RDX‐CMDB propellants are improved with increasing mNPF content. The plateau burning rate of a RDX‐CMDB propellant can be increased to 19.6 mm s⁻¹ when 1.0 % mNPF is added, and the corresponding plateau combustion region occurs at 8–22 MPa.     

Studying the Thermal Properties of a Cotton/Epoxy Composite Inhibitor

The inhibitory effect of double‐base solid propellants is used to control and prevent the burning degree of exposed areas, induced by longer burning time. In recent years, inhibition with cellulose derivatives including cellulose acetate and ethyl cellulose has become popular, but these monolithic systems usually suffer from the drawback of a high erosion rate and demand high thickness and low burning time. A composite inhibitor based on cotton fibers/epoxy resin containing some chlorinated flame retardants (CFR), which were added in inhibitor composition to control its burning process, is described in this article. The thermal properties of the composite inhibitor were studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and flame retardancy. Finally, the inhibited propellant charge, statically fired at ambient temperature, was found to display a smooth and flat pressure‐time profile, confirming the successful performance of the composite inhibition system without the application of any barrier coat.     

Theoretical Analysis of Plasma Enhancement of Propellant Burning Rate

A theoretical model of the combustion of a nitramine solid propellant in the presence of a plasma jet is proposed. Unlike standard double‐base compositions, nitramine propellants exhibit experimental evidence that plasma induces a burning rate enhancement. The model is based on heat transfer considerations and proposes a closed‐form solution of the enhancement of the propellant burning rate as a function of the thermophysical parameters of the system. The model provides a good qualitative agreement with experimental results.