用照度计测定固体推进剂燃烧的火焰温度分布

本文介绍了用照度计测定固体推进剂燃烧火焰温度分布的原理、方法和装置。用标准温度灯验证了该测试系统。在常压、室温下测定了两种双基推进剂和一种复合推进剂的燃烧火焰温度分布。实验指出:双基推进剂的燃烧火焰温度分布符合稳态的燃烧模型,而复合推进剂燃烧的多次实验证明:在火焰相对长度20％和80％附近分别存在两个高温燃烧区;在火焰相对长度40％附近,存在着低温燃烧区。     

DNTF-CMDB推进剂的燃烧机理（英文）

采用燃烧火焰单幅照相技术、微热电偶测温和扫描电镜-能谱仪研究了DNTF-CMDB推进剂的火焰结构、燃烧波温度分布、熄火表面形貌及元素分布。结果表明,含10%DNTF改性双基推进剂的火焰结构为预混火焰,其燃烧波结构与双基推进剂类似。含50%DNTF改性双基推进剂的火焰结构为扩散火焰,其燃烧波结构与AP-HTPB复合推进剂类似。燃烧表面炭物质的减少是推进剂压强指数升高的主要原因。     

NEPE推进剂的燃烧转爆轰特性

介绍了燃烧转爆轰的研究方法、表征参数和影响因素.用DDT管、光电管、应变片、验证板研究了NEPE推进剂混合过程中的燃烧转爆轰特性.研究结果表明,NEPE推进剂药浆的诱导爆轰距离与其在DDT管中的装填密度存在典型的U形曲线关系;当实际装填密度大于理论装填密度的95%时,NEPE推进剂药浆在试验条件下无法发生燃烧转爆轰,同时,NEPE推进剂药浆的诱导爆轰距离与DDT管的破碎程度具有较好的相关性,诱导爆轰距离越小,DDT管的破碎程度越严重.由于立式混合机的密闭性及混合过程中推进剂药浆的不均匀性,NEPE推进剂在混合过程中存在燃烧转爆轰的可能性.     

低铝含量NEPE推进剂燃烧性能研究

研究了铝粉含量为8％的NEPE推进剂。采用配浆浇铸法制备推进剂，并用恒压静态燃速仪测试了推进剂的燃烧性能。考察了NG／DEGDN的比例、AP粒度、HMX粒度对燃速及燃速压力指数的影响。发现增大NG／DEGDN的比例、减小AP粒径或增加细粒度AP含量，将提高NEPE推进剂的燃烧速度，压力指数升高；而HMX粒度降低，NEPE推进剂燃速降低，压力指数降低；不同来源的PbCO3对NEPE推进剂燃烧性能影响很大。     

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.     

燃烧催化剂对含CL-20无烟NEPE推进剂燃烧性能的影响

采用靶线法测试了2~15MPa下含CL-20无烟NEPE推进剂的燃速,通过调节不同种类燃烧催化剂(铅盐、铜盐和炭黑)及其复配催化剂,研究了催化剂对含CL-20无烟NEPE推进剂燃烧性能的影响。分析了含CL-20和催化剂的无烟NEPE推进剂的催化作用机理。结果表明,随着CL-20含量的增加,推进剂的燃速明显增大,当CL-20质量分数为30%时,15 MPa下推进剂的燃速可提高68%。与单组分催化剂和多组分催化剂相比,复配后的双组分燃烧催化剂对推进剂燃速的催化效果最明显,含NTO-Pb/AD-Cu复配催化剂的推进剂在15MPa下的燃速增至25.66mm/s。φ-Pb/乙炔炭黑燃烧催化剂使推进剂在10~15MPa出现平台燃烧,燃速压强指数降至0.22,在2~15MPa下降至0.52。     

含AP包覆硼的富燃推进剂燃烧机理研究

通过微热电偶测温和火焰单幅照相技术测试了含硼富燃料推进剂燃烧波温度分布及燃烧火焰结构;用扫描电镜对熄火表面形貌进行了观察,并通过能谱仪进行局部元素分析;对DSC曲线进行积分,得到推进剂的凝相放热量;测量推进剂燃烧的爆热和低压燃速,获得了其低压燃烧特性和一次燃烧放热情况。结果表明,含AP包覆硼的推进剂燃烧更剧烈,推进剂的绝热火焰温度更高,AP包覆硼提高了含硼富燃料推进剂的凝相放热、爆热和低压燃速。初步确定了该类推进剂的燃烧过程,为建立含硼富燃料推进剂燃烧物理模型提供了依据。     

B12H12［N(C2H5)4］2对NEPE推进剂燃烧性能的影响

研究了硼氢化合物 B1 2 H1 2 [N(C2 H5 ) 4] 2 对 NEPE推进剂燃烧性能的影响 ,采用 DSC分析了 B1 2 H1 2 [N(C2 H5 ) 4] 2 与 NEPE推进剂主要组分硝酸酯的相容性以及对推进剂固化反应的催化作用和对高氯酸铵、硝胺常压热分解的催化作用 ,并利用恒压静态燃速仪测试了推进剂在 4～ 1 1 MPa的燃烧速度和燃速压力指数     

铅盐对无烟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以及熄火表面元素分析,研究了3种铅盐(LF、LP和LC)对无烟NEPE推进剂燃烧性能的影响。结果表明,LF、LP或LC使该推进剂的压强指数在3～5MPa压力范围内降至0.33～0.48,5～12MPa降至0.18～0.58。推进剂熄火表面元素分析结果表明,LF和LP中的铅元素在推进剂燃烧过程中更易于在燃面富集,而LC中铅元素在燃面上的富集程度相对较弱,这与3种铅盐对无烟NEPE推进剂的燃速催化效果一致。     

环境气体氧含量对NEPE推进剂激光点火过程的影响

为研究环境气体氧含量对硝酸酯增塑聚醚(NEPE)推进剂激光点火过程的影响,采用CO2激光辐射点火并利用高速摄影仪记录NEPE推进剂的点火过程,讨论了环境气体氧含量对NEPE推进剂初焰位置与点火延迟时间的影响。结果表明,当环境气体氧含量小于NEPE推进剂热解产物中氧化性气体含量时,NEPE推进剂点火的气相反应发生在推进剂热解产物的分散区,初焰紧靠NEPE推进剂表面,环境气体氧含量变化不影响NEPE推进剂的点火延迟时间;当环境气体氧含量大于NEPE推进剂热解产物中氧化性气体含量时,NEPE推进剂点火的气相反应发生在推进剂热解产物与环境气体的扩散区,初焰远离NEPE推进剂表面,此时由于扩散区氧含量高于NEPE推进剂热解产物分散区氧含量,NEPE推进剂的点火延迟时间减小。     

Experimental Research of the Effects of Superfine Aluminum Powders on the Combustion Characteristics of NEPE Propellants

The combustion behavior of grading aluminum powders containing superfine aluminum powder (SAl) in NEPE propellant has been studied by several kinds of experimental techniques. The results indicate that the usage of grading aluminum powders containing SAl can effectively improve the combustion characteristics of NEPE propellant and the combustion efficiency of aluminum. The reason is that SAl has the different combustion and thermochemical properties from those of generally powdered aluminum (Al). SAl is inclined to burn in a single step, hence greatly increasing the heat released during the thermal decomposition of NEPE propellant.     

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.     

基于图像传感器的推进剂发烟量测试方法

提出了一种基于图像传感器的推进剂发烟量测试方法。用平行光管代替传统测试装置中的卤素钨灯,用图像传感器代替传统测试装置中的光电二极管或光敏电阻,设计了一种表面有镂空条纹的遮光罩对光源信号进行调制,采取图像数据处理方法消除环境噪声对测试结果的影响。测量了SQ2推进剂、Al-CMDB推进剂和NEPE推进剂燃烧烟雾的发烟量。结果表明,SQ2推进剂和Al-CMDB推进剂的烟雾透过率曲线在点火后50s左右基本稳定;NEPE推进剂燃烧的烟雾光透过率曲线在点火50s后稳定,但有缓慢上升趋势;3种推进剂烟雾光透过率分别为84.1%、65.9%、22.3%,与传统测试方法一致。     

Comparative Study on Infrared Irradiance Emitted from Standard and Real Rocket Motor Plumes

The infrared irradiance signature from exhaust plume is essential for the design of solid rocket motors. To overcome the difficulty of conducting experiments using real rocket motors, experimental studies were carried out to compare standard rocket motors and real rocket motors of the same propellant. The static firing tests on standard and real rocket motors of NEPE and HTPB propellants were conducted. Despite different rocket motor size and methodology of spectro‐radiometric measurement, the spectral characteristics of the infrared irradiance signature for both rocket motors were quite similar. The standard and real rocket motors of HTPB propellant showed similar tendency of steady infrared irradiance emission throughout the combustion, whereas both rocket motors of NEPE propellant showed a rapid emission in the midstream of combustion. The total infrared irradiance of NEPE was about 55 % less than that of HTPB propellant for both standard and real rocket motor experiments. Additionally, the relative amounts of chemical products produced during propellant combustion came out to be similar for both rocket motors. The experimental results indicated that the spectral characteristics of infrared irradiance and combustion products were quite similar for different sized rocket motors of same propellant and that a correlation of infrared irradiance signature exists between small‐sized standard rocket motors and real rocket motors. Thus, the spectral characteristics of real rocket motors could be reasonably estimated from the results of standard rocket motors.     

钾盐对发射药静态燃烧烟焰性能的影响

为研究钾盐对发射药静态燃烧烟焰性能的影响,以含钾盐的发射药样品为对象,采用单幅放大彩色摄影法、微热电偶测温法以及双光路透射率系统,研究了硫酸钾(K2SO4)、硝酸钾(KNO3)、新型有机钾盐(DK、HK、LK、JK和PK)等对发射药燃烧时的火焰形貌、火焰峰温、烟雾可见光透光率的影响。结果表明,无机钾盐K2SO4对发射药静态燃烧火焰大小和峰温的抑制效果最好,但会使发射药静态燃烧时的烟雾可见光透过率大大降低;高氧含量的新型有机钾盐DK、HK及LK对发射药静态燃烧火焰大小和峰温有较好的抑制效果,并且含新型有机钾盐的发射药静态燃烧时的烟雾可见光透过率较高,3种含高氧含量钾盐(LK、DK和HK)的发射药的烟雾可见光透过率均大于50%;钾盐的粒径从104μm减小到5μm时,消焰效果得到提高,但烟雾可见光透过率的变化规律并不一致。     

NEPE推进剂拉伸断裂行为研究

通过单向拉伸力学性能实验,考察了不同测试温度和不同拉伸速率条件下NEPE推进剂力学性能的变化情况。采用扫描电镜(SEM)和原位拉伸SEM观察了推进剂拉伸断面形貌。结果表明,在低温测试条件下,NEPE推进剂最大伸长率较常温条件下显著降低,最大抗拉强度较常温和高温条件下显著升高,NEPE推进剂的破坏主要表现在黏合剂的撕裂和固体颗粒的断裂;在高温、慢拉伸速率的测试条件下,推进剂断裂时结构被破坏的程度较大,NEPE推进剂的破坏首先发生在固体颗粒堆积处,再到黏合剂网络结构。推进剂断裂的过程是推进剂拉伸取向与裂纹扩展之间的竞争过程。     

星型PAO黏合剂在NEPE推进剂中的应用

星型PAO作为一种新型高能固体推进剂用黏合剂,其特有的3星或4星结构,能提高NEPE推进剂交联网络的交联比例,且交联点间有较长的柔韧结构,能充分抵抗拉长和撞击的破坏,可有效改善NEPE推进剂的力学性能,并在一定程度上降低推进剂的感度。文中主要对星型PAO的结构特点及其在NEPE推进剂中的应用情况进行了评述和总结。     

Infrared Irradiance Reduction in Minimum Smoke Propellants by Addition of Potassium Salt

One of the plume characteristics of minimum smoke propellant is the infrared (IR) radiation signature, which may be useful for detection of rocket. The IR irradiance is known to be reduced by afterburning suppression in rocket plume by addition of potassium salt in propellant. The minimum smoke propellant with nitrate ester polyether (NEPE) binder system and nitramine oxidizers was researched for the afterburning and IR irradiance difference according to the content of potassium salt as afterburning suppressant in propellant formulation. The propellants were formulated to satisfy the level of AGARD smoke class AA and potassium sulfate was selected as afterburning inhibitor suitable for NEPE propellant. The afterburning flame length and mid‐range IR intensity were measured, while conducting static firing tests of 6 inch (15.24 cm) standard rocket motors loaded with minimum smoke propellants of the different contents of potassium sulfate. The total IR irradiance of HMX/RDX propellant with 1.1 % potassium sulfate was reduced to about 23 % compared to the propellant without afterburning suppressant due to the inhibition of afterburning. Also, the total IR irradiance of the HNIW (30 %)/RDX propellant was found to be almost three times more than that of the HMX/RDX propellant although the content of potassium sulfate was the same of 1.1 % in both propellants.