翼型动态特性数值模拟及其影响因素分析

采用非结构动网格技术模拟了NACA 0012翼型绕1/4弦长位置俯仰的强迫振荡过程，验证了翼型的周期性动态气动特性。分析了不同的湍流模型、单周期内步数和内迭代次数等因素对计算结果的影响；研究了马赫数和减缩频率对动态气动迟滞特性的影响。结果表明， Transtion SST模型得到的结果更准确；单周期内计算步数大于200时，计算结果收敛性更好；随着马赫数变大，迟滞效应先增大后减小；在亚音速区，迟滞环沿逆时针方向，动导数小于零，模型动稳定；而在跨音速区，迟滞环沿顺时针方向，动导数大于零，模型动不稳定；减缩频率越大，翼型动态迟滞效应越明显。

Numerical Simulation of Airfoil Dynamic Aerodynamics and Analysis of its Influencing Factors

Forced oscillation of NACA 0012 airfoil pitching at 25% chord was simulated with unstructured dynamic mesh and unsteady hysteresis characteristics was verified. Effects of different turbulence models, timesteps and inner iterations on aerodynamic characteristics were all analyzed. The results show that the results with Transition SST model are better than others;If the timestep is more than 200,the results are better;As Mach number increases,the hysteresis effects first increase then decrease;At subsonic speed, the hysteresis circles anti-clockwise and the dynamic derivatives are smaller than zero and the model is stable;While at transonic speed,the hysteresis circles clockwise and the dynamic derivatives are bigger than zero and the model is unstable; The bigger reduced frequency, the more obvious the hysteresis effects.