Silica and titania nanoparticles were included at mass loadings of 1% and 3% in aqueous HAN propellants to evaluate their effects on liquid- and gas-phase decomposition and combustion. Both the liquid-phase and overall burning rates of propellant formulations were indirectly measured in a constant-volume strand burner filled with Argon from pressures of 3–22 MPa using a novel, pressure-based method developed by the authors in recent work. This approach provides overall burn times for propellants such as aqueous HAN which continue to burn beyond the disappearance of the liquid, making it superior to methods based solely on visual observation which only monitor the liquid surface regression. The presence of silica nanoparticles increased the liquid-phase burning rate in the low- and medium-pressure regimes (<10 MPa) and increased the overall burning rate at all pressures evaluated. The maximum amount of burning rate enhancement was realized at the lowest evaluated pressure (3 MPa) which corresponded to 80% and 670% increases in the liquid-phase and overall burning rates, respectively, for a silica loading of 1%, and 160% and 830% increases in the liquid-phase and overall burning rates, respectively, for a silica loading of 3%. The presence of titania did not measurably affect the liquid-phase burning rate, but it did increase the overall burning rate in the low-pressure regime (<5.7 MPa). This low-pressure overall burning rate enhancement was not amplified by further titania loading from 1% to 3% and was maximized at the lowest evaluated pressure (3 MPa) which corresponded to a 500% increase in the overall burning rate. The observed enhancements of the propellant's liquid-phase and overall burning rates were attributed to the presence of catalytic processes which diminish at higher pressures. This work represents the first time nanoparticle additives have been utilized to tailor the combustion of liquid HAN-based monopropellants.

二氧化硅和二氧化钛纳米粒子的质量含量分别为HAN推进剂的1％和3％，以评估它们对液相和气相分解和燃烧的影响。推进剂配方的液相燃烧速度和总燃烧速度都是使用作者在最近的工作中开发的一种新颖的基于压力的方法，在3-22 MPa的压力下，在充满氩气的定容线束燃烧器中间接测量的。这种方法为HAN等推进剂提供了总体燃烧时间，这些推进剂继续燃烧超过液体消失，使其优于仅基于视觉观察的方法（仅监视液体表面消退）。二氧化硅纳米粒子的存在提高了低压和中压条件下的液相燃烧速率（< 10 MPa），并提高了在所有评估压力下的总体燃烧速率。在最低评估压力（3 MPa）下实现了最大的燃烧速率增强，在二氧化硅负载量为1％和160％的情况下，液相和整体燃烧速率分别增加了80％和670％当二氧化硅的负载量为3％时，液相和整体燃烧速率分别提高了830％和830％。二氧化钛的存在并未显着影响液相燃烧速率，但确实在低压状态（<5.7 MPa）下提高了总燃烧速率。进一步的二氧化钛负载量从1％增至3％不会增强这种低压总体燃烧速率的提高，并且在最低评估压力（3 MPa）时达到最大值，这相当于总体燃烧速率提高了500％。所观察到的推进剂液相和总体燃烧速率的提高归因于催化过程的存在，该催化过程在较高压力下会减弱。这项工作代表了纳米颗粒添加剂首次用于调整液态HAN基单推进剂的燃烧。