LOX/GCH₄ pintle injector is suitable for variable-thrust liquid rocket engines. In order to provide a reference for the later design and experiments, three-dimensional numerical simulations with the Euler-Lagrange method were performed to study the effect of the initial particle diameter on the combustion characteristics of a LOX/GCH₄ pintle rocket engine. Numerical results show that, as the momentum ratio between the radial LOX jet and the axial gas jet is 0.033, the angle between the LOX particle trace and the combustor axial is very small. Due to the large recirculation zones, premixed combustion mainly occurs in the injector wake region. As the initial LOX particle diameter increases, the LOX evaporation rate and the combustion efficiency decrease until the combustion terminates with the initial LOX particle diameter greater than 110 μm. The oscillation amplitude of the combustor pressure increases significantly along with the increase of the initial LOX particle diameter, and the low-frequency unstable combustion occurs when the initial LOX particle diameter exceeds 60 μm. The combustor pressure oscillation at about 40 Hz couples with the swinging process of spray and flame, while the unsteady LOX evaporation amplifies the combustor pressure oscillations at 80 Hz and its harmonic frequency.

中文翻译：

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LOX粒径对气液活塞发动机燃烧特性的影响。

LOX / GCH ₄针形喷油器适用于可变推力液体火箭发动机。为了给以后的设计和实验提供参考，使用欧拉-拉格朗日方法进行了三维数值模拟，以研究初始粒径对LOX / GCH ₄燃烧特性的影响。皮特尔火箭发动机。数值结果表明，当径向LOX射流与轴向气体射流之间的动量比为0.033时，LOX粒子迹线与燃烧室轴向之间的夹角很小。由于较大的再循环区域，预混燃烧主要发生在喷射器尾流区域。作为初始LOX粒径增大，LOX蒸发速率和燃烧效率降低，直到与初始LOX粒径大于110的燃烧终止 μ米。燃烧器压力的振荡幅度显著沿着与初始LOX粒径的增加而增加，并且当初始LOX粒径超过60发生的低频不稳定燃烧 μ米 燃烧器压力振荡在约40 Hz时与喷雾和火焰的摆动过程耦合，而不稳定的LOX蒸发会放大80 Hz及其谐波频率下的燃烧器压力振荡。