考虑弹性影响的乘波体飞行动力学特性

针对典型的吸气式乘波体构型高超声速飞行器,研究了结构弹性对纵向静态特性和飞行动力学特性的影响.使用当地流活塞理论给出了高超声速非定常气动力模型,并结合简化的超燃冲压发动机模型及弹性机体结构模型,建立了考虑气动/结构/推进耦合的飞行器非线性纵向动力学模型.基于该模型分析了机体弯曲刚度变化对飞行器定常平飞配平参数、飞行包线以及动力学系统开环零极点的影响.结果表明:机体结构刚度降低将使配平升阻比减小,动稳定性变差,并且当其低于某一临界值时,升降舵配平特性将由正操纵变为反操纵.

Elastic effects on flight mechanics of waverider

The impact of structural elasticity on the static properties and dynamic stability of a typical air-breathing hypersonic vehicle was investigated.An integrated aeropropulsive/aeroelastic model was developed for the longitudinal dynamics of hypersonic vehicles,with local piston theory for unsteady aerodynamics.A comparative analysis of level-flight trim control,trimmable region,open-loop poles and non-minimum phase zeros was performed when the fuselage was subjected to different bending stiffness.The results show that the structural elasticity has a significant influence on the flight mechanics of hypersonic waverider.The elevator operation mode of vehicles with flexible fuselage is reversed in high Mach number zone.As the fuselage bending stiffness decreases,the lift-drag ratio drops and dynamic stability deteriorates.