Abstract

Composite propellants are tested using the quench particle collection bomb (QPCB) for the pressure ranging from 2 to 8 MPa to estimate the particle size distribution of aluminum agglomerates from quenched combustion residues emerged out from the burning surface. The major ingredients included in the propellants are ammonium perchlorate (AP), aluminum (Al), hydroxyl-terminated polybutadiene (HTPB), and toluene diisocyanate (TDI). Five propellant compositions are considered in this study; two of them are mixed with catalysts. Propellant formulation variables like the coarse AP/fine AP ratio, total solid loading, catalyst percentage, and aluminum content are varied to assess their effects on the aluminum agglomeration process at different pressures. Unburnt aluminum in agglomerates is continuously getting combusted as they move out from the propellant burning surface. Large agglomerates comprise both Al₂O₃ and unburnt aluminum. The majority of agglomerates are spherical in shape, and the sizes vary from 31 to 115 \(\mu\)m for non-catalyzed propellants and from 28 to 136 \(\mu\)m for catalyzed propellants over the tested pressure conditions. These results can give further insight into the aluminum agglomeration process of catalyzed and non-catalyzed propellants and also affect the choice of the propellant ingredient percentage aimed at reducing aluminum agglomeration, which causes two-phase flow losses of thrust and slag accumulation in full-scale solid rocket motors.

中文翻译：

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催化复合推进剂中铝的团聚与燃烧研究

摘要

使用淬火颗粒收集弹（QPCB）对复合推进剂进行测试，其压力范围为2到8 MPa，以估算从燃烧表面冒出的淬火残余物估算出的铝附聚物的粒度分布。推进剂中包括的主要成分是高氯酸铵（AP），铝（Al），羟基封端的聚丁二烯（HTPB）和甲苯二异氰酸酯（TDI）。本研究考虑了五种推进剂成分。它们中的两个与催化剂混合。改变推进剂配方变量，例如粗AP /细AP比，总固含量，催化剂百分比和铝含量，以评估它们在不同压力下对铝团聚过程的影响。结块中未燃烧的铝从推进剂燃烧表面移出时会不断燃烧。大型附聚物同时包含铝₂ O ₃和未燃烧的铝。大部分团聚物的形状为球形，并且尺寸变化从31到115 \（\亩\）米非催化的推进剂和从28到136  \（\亩\）米用于在测试压力条件下催化推进剂。这些结果可以进一步了解催化和非催化推进剂的铝团聚过程，还可以影响旨在减少铝团聚的推进剂成分百分比的选择，从而导致推力和炉渣积累的两相流损失。固体火箭发动机。