目前,导弹推进技术已发展到一个新阶段,即助推火箭发动机和冲压主发动机可以整装在同一导弹之中。这种结构的优点是,可以使导弹的形状、尺寸和重量易于达到最佳化;由于两种发动机连续工作,又可同用一个燃烧室;而且,火箭发动机还能用来预热冲压发动机燃料。为使火箭和冲压发动机都能有效的工作,各个发动机必须有与此相适应的喷管。由于冲 At present, the missile propulsion technology has been developed to a new stage, that is, the booster rocket engine and the main engine of the press can be integrated into the same missile. The advantage of this structure is that the shape, size and weight of the missile can be easily optimized; a single combustion chamber can be used with both engines working continuously; and the rocket motor can also be used to preheat the ramjet fuel . For the rocket and ramjet engines to work effectively, each engine must have a compatible nozzle. Because of red