整体式液体冲压发动机

INTEGRATED LIQUID FUEL RAMJET ENGINE

关键词:  火箭冲压发动机  点火  振动  防热

Key words:  Rocket ramjet  Ignition  Vibration  Heat protection

摘要:

整体式冲压发动机是将固体助推火箭与巡航用液体燃料冲压发动机组合成为一个整体的新型动力装置,它是超声速、小体积、中远程导弹动力系统的最佳选择.整体式冲压发动机的出现将冲压发动机的应用推向一个新阶段,引起世界各国的广泛重视.近几年我国在整体式冲压发动机很多关键技术的研究上有所突破.液体冲压发动机和助推火箭共用一个燃烧室,使燃烧室中无法安装专门的机械式火焰稳定器和空气冷却衬筒,这为解决燃烧室的点火起动问题、振动问题及热防护问题带来了很大的困难.试验表明:冲压发动机的点火起动问题有多种解决方案,其中火焰稳定性准则的满足是点火起动的重要条件;燃烧室的进口流场,燃油浓度分布等对振动有很大的影响;计算表明,冲压发动机在飞行状态时,流经燃烧室壳体外表面的高速气流的冷却作用可大大降低燃烧室壳体的温度,在相同的冷却效果下,可降低对热防护层的要求.

Abstract:

The integrated ramjet which consists of a liquid fuel ramjet and a solid fuel booster is a new type of engine.It is the best choice for the propulsion system of supersonic, small volume, medium-and long-range missile.The integrated ramjet has Wide field of application and is drawing attention from the world.In recent years, China has advanced greatly in the key technology of integrated ramjet. Since the liquid fuel ramjet and the booster share the same combstor,neither mechani cal flame-holder nor air film cooling structure can be installed in the combustor.This causes some difficulty in design of ignition,combustion oscillation reduction and themal protection,However test results show :several methods can be used for solving the problem of ignition,and one of the keys is to meet the flame stability criteria.The flow field of combustor inlet,and the fuel distribution, etc.have a great effect on the combustion oscillation. The computation results also show: during flight, the high velosity airstream outside the wall of combustor can greatly reduce the temperature of the combustor wall,and as a result the challenge for thermal protection struction with the same cooling effect is reduc-ed.