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地面颤振模拟试验作为一种颤振研究的新方法,可以有效地弥补传统气动弹性试验的不足。对地面颤振模拟试验的主要难点,即非定常分布式气动力集成减缩加载的方法开展研究:基于亚声速偶极子格网法和活塞理论建立了亚声速以及超声速翼面的非定常气动力模型,通过曲面样条插值以及有理函数拟合获得了试验时域减缩气动力;提出以颤振关键模态的振型为优化目标,使用遗传算法搜寻气动力最优减缩位置的优化方法;建立了闭环系统的时域状态空间模型,使用颤振时域仿真结果与频域理论结果进行对比,对比发现二者误差可控制在3%以内。研究结果表明,该文提出的非定常气动力模拟方法可以很好地表征翼面非定常气动力分布特性,可以作为地面颤振模拟试验研究可靠的理论基础。
As a new method of flutter research, ground flutter simulation test can effectively make up for the deficiency of traditional aeroelasticity test. The main difficulty of the ground flutter simulation test is the unsteady distributed aerodynamic integration and reduction loading method. The unsteady aerodynamic forces of subsonic and supersonic airfoils are established based on subsonic dipole grid method and piston theory Model, the aerodynamic force was obtained by fitting the surface spline interpolation and the rational function fitting. The optimization model was proposed based on the vibration mode of the critical mode of flutter, and the genetic algorithm was used to search for the optimal method of aerodynamic optimum reduction and contraction. The time-domain state space model of the closed-loop system is compared with the results of the frequency-domain theory by using the time-domain chatter simulation results. The comparison shows that the error between the two can be controlled within 3%. The results show that the proposed unsteady aerodynamic modeling method can characterize the unsteady aerodynamic characteristics of the airfoils and can be used as a reliable theoretical basis for ground flutter simulation experiments.