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固体火箭发动机实验条件下,对4D编织C/C复合材料变参数流道拉瓦尔喷管进行了烧蚀特性研究。针对变流道喷管变化的烧蚀角度,分析了材料的烧蚀机理。结果表明,由于变流道的原因,从收敛段到喉部烧蚀逐渐加剧,在收敛段与喉部过渡段45°烧蚀角出烧蚀最为严重,烧蚀角越大,烧蚀越严重。之后,烧蚀程度明显逐渐减小。烧蚀率沿着变流道喷管轴向逐渐改变,最大烧蚀率是0.056 mm/s,最大质量烧蚀率是0.157 kg/m~2·s。并且,轴向纤维、径向纤维到环向纤维,烧蚀尖角逐渐增大。烧蚀特性与粒子速度、粒子撞击角度、粒子浓度、壁面剪切力等因素相关。在热化学烧蚀和机械剥蚀共同作用下,变流道是不同烧蚀行为的主要影响因素。
Solid rocket motor experimental conditions, 4D braided C / C composite variable parameter flow channel Laval nozzle ablation characteristics were studied. Aiming at the ablation angle of variable nozzle, the ablation mechanism of the material was analyzed. The results show that the ablation from the convergence zone to the larynx gradually aggravates due to the variable flow path, and the ablation angle is the most serious at the 45 ° ablation zone in the convergent section and the laryngeal section. The larger the ablation angle, the more severe the ablation . After that, the degree of ablation decreased significantly. The ablation rate gradually changes along the axis of the nozzle. The maximum ablation rate is 0.056 mm / s and the maximum ablation rate is 0.157 kg / m ~ 2 · s. And, axial fibers, radial fibers to the circumferential fiber, ablation sharpness gradually increased. Ablation characteristics and particle velocity, particle impact angle, particle concentration, wall shear and other factors. Under the combined action of thermal chemical ablation and mechanical ablation, the variable flow path is the main influencing factor of different ablation behaviors.