复合推进剂燃烧性能与组分热分解特性的关系实验研究

应用常压和高压差热分析技术研究了催化剂对推进剂组分热分解的影响,测定了催化剂共晶和混合加入时相应推进剂的燃速,分析了热分析与推进剂燃烧过程的异同点,引入高氯酸铵(AP)高温分解起始温度(T_(L-H))的概念并以T_(L-H)衡量了催化剂共晶加入时对丁羟推进剂燃速和压力指数的影响.研究表明,AP高温分解过程对复合推进剂燃烧特性影响较大;热分析与燃速相关性和催化剂加入方式有关;共晶催化剂作用下的复合推进剂燃速特性与氧化剂高温分解有密切关系;压强是影响推进剂燃速和热分解相关性的重要因素,高压下AP高温分解过程和变化能更大程度地反映到推进剂燃速中去。本文同时对产生上述现象的原因作了分析。     

固液火箭发动机性能特征

介绍了国外固液火箭发动机研制的进展。阐明了固液发动机比冲、可多次启动—关机、推力可调、安全性好和成本低等特点。分析了固液发动机推进剂的燃烧特性和发动机性能特性、与液体和固体火箭发动机的不同，以及研制的技术难度等。最后探讨了固液火箭发动机的应用范围。     

介绍几种液体燃料小滴燃烧的落塔试验方案

本文简要介绍微重力条件下液体燃料小滴燃烧研究中，所采用的几种塔试验方法及试验设备。给出了单滴静态燃烧，运动小滴的燃烧，小滴列燃烧等的试验装置图。     

液体火箭发动机后效冲量的测量方法

本文叙述在地面条件下试验液体火箭发动机时,通过测量发动机后效段推力与测量发动机燃烧室压力两种方法来求得模拟高空后效冲量,并对这两种方法作简单评论。     

球烯在RDX—CMDB推进剂中作用初探

将球烯引入ＲＤＸ－ＣＭＤＢ推进剂中，通过燃速测试和热分析试验发现，在保持压强指数不变的前提下，含球烯推进剂可使燃烧提高约４ｍｍ／ｓ。同时指出球烯很可能是固体推进剂良好的催化载体；它对于改善固体推进剂的其它多种性能可能都具有潜在的优越性。     

铅盐、铜盐及其碳黑复合物对叠氮/硝胺推进剂燃烧性能的影响

研究了LA铅盐、GT铜盐及其碳黑复合物对硝胺/叠氮推进剂燃烧性能的影响。结果表明：GT铜盐可提高叠氮/硝胺推进剂的燃速,质量分数1%的GT铜盐能提高推进剂燃速1.5～2.4 mm/s;LA铅盐、GT铜盐及其碳黑复合物可降低叠氮/硝胺推进剂压强9～19 MPa下的压强指数,推进剂中加入质量分数3%的该复合催化剂,压强9～...     

冲压发动机模型燃烧室低压燃烧性能试验

低压不利于燃烧,从化学动力学角度分析,压力降低导致空气密度降低,化学反应速率降低。用冲压发动机模型燃烧室进行了低压燃烧试验,结果显示：进口压力pin从0.094 MPa变至0.065 MPa,燃烧效率由大变小;压力降低到0.065 MPa时,燃烧室燃烧性能急剧恶化,燃烧极不稳定,随时可能因压力波动或油气参数变化而熄火。无传焰槽时燃烧效率随压力的变化规律与有传焰槽的一致,但燃烧效率相对低一些。     

直射式喷孔后方燃油浓度场计算及其分析

由于直射式喷油孔的结构简单、布置和调整方便,因此已被广泛地应用于冲压发动机的燃烧室中,而且喷孔后方的燃油浓度分布对火焰稳定及燃烧效率有很大影响,由此预知喷孔后方燃油浓度分布对喷孔布置、确定喷孔与稳定器的相对位置是十分重要的。根据试验结果,推导得到了直射式喷孔后方燃油浓度分布的计算公式,编制燃油浓度分布的计算程序,以分析直射式喷油孔后方的燃油浓度场分布。     

Experimental study of entrainment phenomenon in a trapped vortex combustor

Trapped vortex combustor (TVC) is an advanced low-pollution gas turbine combustor, with the adoption of staged combustion technique. To achieve low-pollutant emission and better combustion performance, the proportion of the air flow in each combustion zone should be precisely determined in the design of the combustor. Due to the presence of entrainment phenomenon, the total air flow in the cavity zone is difficult to estimate. To overcome the measurement difficulty, this study adopts the indirect measurement approach in the experimental research of entrainment phenomenon in the cavity. In accordance with the measurement principle, a TVC model fueled by methane is designed. Under two experimental conditions, i.e. with and without direct air intake in the cavity, the influence of the mainstream air flow velocity, the air intake velocity in the cavity, the height of inlet channel, the structure of holder and the structural proportion of the cavity on entrainment in the cavity is studied, respectively, through experiment at atmospheric temperature and pressure. The results suggest that the air flow velocity of mainstream, the air intake velocity of the cavity and the structure of the holder exert significant influence on the air entrainment, while the influence of structural proportion of the cavity is comparatively insignificant. The square root of momentum ratio of cavity air to mainstream air could be used to analyze the correlation of the entrainment data.     

An efficient regulation approach for tomographic reconstruction in combustion diagnostics based on TDLAS method

For tomographic reconstruction in combustion diagnostics, it is usually necessary to solve a rank-deficient problem, where the number of non-linear dependent equations is smaller than the number of unknowns. In some reconstructions, there are grids without rays passing through. This produces artifacts during the reconstruction. In this paper, the weight of the regulation equation is modified with the number of the rays crossing the grid cells. The effect of the neighboring grid values as well as the number of rays crossing the grid cells is considered in the new regulation method. Numerical simulation results show that the new regulation method suppresses the reconstruction error of the no rays crossing grid and successfully restrains the corner distortion in four projection angles. The effects of the weight coefficient and the smoothing factor on the reconstruction are examined through a numerical study. Finally, a combustion experiment demonstrates that the new regulation method can significantly reduce the reconstructed error, especially for the non-ray crossing condition, and the results are compared with thermocouple measurements and reconstructions without modified regulation.