摘要
针对直升机大机动飞行仿真,建立了一个非线性的飞行动力学模型,考虑了翼型非定常/动态失速、机动飞行引起的动态尾迹畸变、桨叶弹性变形效应和发动机动态特性。采用基于有限元分析的挥舞-摆振-扭转耦合的弹性桨叶模型,并利用一种新的数值方法将旋翼/机体耦合运动方程表示为显式形式,整个飞行动力学模型表示为状态空间格式。以UH-60A直升机在高速飞行条件下的急拉杆机动飞行为例进行仿真计算,并与飞行试验数据进行对比验证。分析表明,仿真结果与试验结果吻合,高速飞行条件下机体抬头过程中前行桨叶非定常气动载荷的计算误差是引起旋翼和机体运动仿真误差的主要原因。
A nonlinear flight dynamics model is established for helicopter large amplitude maneuvering flight simulation which takes into consideration the effects of unsteady aerodynamics and dynamic stall,dynamic wake distortion induced by maneuvers,elastic deformations of blades and engine dynamics.A coupled flap-lag-torsion elastic blade model is formulated based on the finite element method and the coupled rotor/fuselage equations of motion are presented in explicit form using a novel numerical method.Thus,the entire model is presented in finite-state form.As an example,a pull-up maneuver of helicopter UH-60A under high speed flight condition is simulated.The correlation of the results with the flight test data is provided.It is shown that the results agree well with flight test data and the primary contribution to the discrepancy of the simulation of the motions of the rotor and fuselage comes from inaccurate prediction of the unsteady airloads on the blades of the advancing side in the nose-up process.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2010年第12期2315-2323,共9页
Acta Aeronautica et Astronautica Sinica
