The effects of flow structure and particle size in the secondary combustor of a ducted rocket on mixing are investigated using a two-phase large eddy simulation analysis. The corner recirculation zone and central recirculation area appear in the combustor. Vortexes are generated mainly by the axial inlet flow. The stretched eddies along the axial direction appear on the rear section of the combustor. The mainstream in the combustor shows a periodic oscillatory repetition with a frequency of about 1100 Hz. This motion is an essential factor in determining the distribution of droplets. When the size of the particles exceeds 10 micrometers ( $${\rm St}_{\rm k}$$ > 1), the particles do not penetrate the corner recirculation zone. The flow distribution according to the size of the particles does not differ significantly, but the distribution of particles can be very different, which is an important consideration for combustion.

中文翻译：

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粒度和速度比对二次燃烧室流动结构影响的 LES

使用两相大涡模拟分析研究了管道火箭二级燃烧器中流动结构和颗粒尺寸对混合的影响。角部回流区和中心回流区出现在燃烧室中。涡流主要由轴向入口流产生。沿轴向拉伸的涡流出现在燃烧器的后部。燃烧器中的主流显示出频率约为 1100 Hz 的周期性振荡重复。这种运动是决定液滴分布的重要因素。当颗粒尺寸超过 10 微米（$${\rm St}_{\rm k}$$ > 1）时，颗粒不会穿透拐角回流区。根据颗粒大小的流量分布没有显着差异，