The combustion characteristics obtained from the coupling effect between swirl injection and a novel composite hybrid rocket fuel grain were investigated. The novel composite fuel grain was composed of a three-dimensional printed acrylonitrile-butadiene-styrene (ABS) helical substrate with an embedded paraffin-based fuel. Two swirl flow injectors with opposite injection directions were designed: one with the same injection direction as the swirling direction induced by the ABS helical substrate and the other having the opposite direction. Axial injection trials were also performed as a baseline for comparison. Firing tests were carried out using a lab-scale hybrid rocket engine with oxygen as the oxidizer at average mass flux values in the range of 2.1–4.5 g/(s·cm²). When combined with either swirl flow injector, the novel composite fuel grain exhibited excellent combustion properties. Compared with the axial flow injector, both swirl injectors greatly improved the regression rate of the novel composite fuel grain, by 82.4% and 50.6% respectively, at an oxygen mass flux of approximately 4.25 g/(s·cm²). Three-dimensional imaging of the inner surface of the novel composite fuel grain and cold flow numerical simulations were employed to assess the mechanism by which the regression rate was increased. The results of these analyses elucidated the effects of different injection methods on the oxidizer-to-fuel ratio distribution during combustion of the novel composite fuel grain.

研究了旋流喷射与新型复合混合火箭燃料颗粒之间的耦合作用获得的燃烧特性。新型复合燃料颗粒由 3D 打印的丙烯腈-丁二烯-苯乙烯 (ABS) 螺旋基材和嵌入的石蜡基燃料组成。设计了两种具有相反喷射方向的旋流喷射器：一种喷射方向与 ABS 螺旋基板引起的旋流方向相同，另一种方向相反。还进行了轴向注射试验作为比较的基线。使用实验室规模的混合火箭发动机进行点火测试，氧气作为氧化剂，平均质量通量值在 2.1-4.5 g/(s·cm ^2范围内）。当与任一旋流喷射器结合使用时，新型复合燃料颗粒表现出优异的燃烧性能。与轴流式喷油器相比，两种旋流式喷油器在氧气质量流量约为4.25 g/(s·cm ² ) 时，都大大提高了新型复合燃料颗粒的回归率，分别提高了82.4%和50.6%。采用新型复合燃料颗粒内表面的三维成像和冷流数值模拟来评估回归率增加的机制。这些分析的结果阐明了不同喷射方法对新型复合燃料颗粒燃烧过程中氧化剂燃料比分布的影响。