基于亚燃的高超声速冲压发动机内流道研究

Internal flowpath for hypersonic ramjet based on subsonic combustion

为了研究亚燃冲压发动机在高超声速条件下工作的性能,采用总体性能计算方法和流体力学仿真对基于突扩燃烧的高马赫数亚燃冲压发动机内流通道进行匹配设计研究,得到了其速度特性和调节特性.结果表明,设计出的亚燃冲压发动机在高超声速范围内性能良好,能够正常工作.在接力点处,马赫数Ma=3.5,高度H=12 km,得到最大推力系数为0.649,此时比冲为13 801.2 N·s/kg;在巡航点处,Ma=5.0,H=21 km,发动机余气系数α=1.8时,得到推力系数为0.370,此时最大比冲为12 574.0 N·s/kg.研究认为,最大飞行马赫数为5～6的高超声速冲压发动机采用亚燃是可行的.

To explore the performance of subsonic combustion ramjet working at hypersonic incoming flow conditions, the matching of internal flowpath of a ramjet based on dump combustion chamber is studied. The performance of the engine is obtained by means of integrated performance computation and fluid dynamics simulation. The results indicate that the designed subsonic combustion ramjet has good performance at hypersonic incoming flow conditions and works well. At the booster-to-ramjet transition point with Mach number Ma = 3.5, altitude H = 12 km, the thrust coefficient has its maximum value of 0. 649 and the specific impulse is 13 801.2 N · s/kg. At the cruising condition with Mach number Ma = 5.0, altitude H=21 km, excess air coefficient α= 1.8, its specific impulse has its maximum value of 12 574.0 N · s/kg, and the thrust coefficient is 0. 370. This study shows that the hypersonic ramjet with subsonic combustion for the maximum incoming Mach number between 5 and 6 is feasible.