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781.
The study includes the experimental investigation of the evaporation performance of T-type vaporizer,mainly studied the relationship of the inlet air temperature and vaporizer wall temperature with the evaporation ratio.Then,it studied the LBO(lean blow out) and combustion efficiency of the micro aero-engine combustor with T-type vaporizer on the normal pressure test rig.The inlet air condition is environmental pressure and temperature.The gas analysis method is used to study the combustion efficiency,and the inlet air temperature is 300 K,400 K and 500 K.It could be concluded that the evaporation performance is improved with the increasing of the inlet air temperature and vaporizer wall temperature;the average LBO is 0.003;the combustion efficiency rises with the inlet air temperature,and it remain constant when the fuel/air ratio changed in the range from 0.008 to 0.02.The vaporization ratio is the key factor to determine the combustion performance. 相似文献
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为了准确预示固体火箭发动机碳基材料喷管的烧蚀率,依据热化学烧蚀理论,建立了喷管传热烧蚀的二维轴对称气-固-热耦合计算模型,计算通过FLUENT壁面化学反应模型完成,无需事先假设烧蚀控制机制。针对70-lb BATES发动机喷管进行了烧蚀计算,研究了推进剂配方、氧化性组分、燃烧室压强对喷管烧蚀的影响。结果表明:烧蚀率计算值与试验测试值吻合较好;烧蚀率分布遵循喷管内壁热流密度分布规律,在喉部上游入口处达到峰值;烧蚀率随推进剂Al含量增加而降低,随燃烧室压强升高而近似正比例增大;H2O是决定烧蚀的主要氧化性组分。 相似文献
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Nozzle effects on thrust and inlet pressure of a multi-cycle air-breathing pulse detonation engine (APDE) are investigated experimentally. An APDE with 68 mm in diameter and 2 050 mm in length is operated using gasoline/air mixture. Straight nozzle, converging nozzle, converging-diverging nozzle and diverging nozzle are tested. The results show that thrust augmentation of converging-diverging nozzle, diverging nozzle or straight nozzle is better than that of converging nozzle on the whole. Thrust augmentation of straight nozzle is worse than those of converging-diverging nozzle and diverging nozzle. Thrust augmentations of diverging nozzle with larger expansion ratio and converging-diverging nozzle with larger throat area range from 20% to 40% on tested frequencies and are better than those of congeneric other nozzles respectively. Nozzle effects on inlet pressure are also researched. At each frequency it is indicated that filling pressures and average peak pressures of inlet with diverging nozzle and converging-diverging nozzle with large throat cross section area are higher than those with straight nozzle and converging nozzle. Pressures near thrust wall increase in an increase order from without nozzle, with diverging nozzle, straight nozzle and converging-diverging nozzle to converging nozzle. 相似文献
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