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通过求解雷诺平均非定常Navier-Stokes方程,采用数值模拟方法计算了俯仰和沉浮振动对NACA0012翼型平均气动特性的影响。结果表明:对于俯仰运动而言,在迎角α≤13°时的升力和力矩曲线的线性段部分,振幅角的变化对动态平均升力系数和动态平均力矩系数的影响不明显,与静态时的情况基本一致;当迎角α≥14°时,翼型振动的平均升力系数和动态平均力矩系数小于静态时的情况。同一迎角条件下的俯仰振动频率越高时,其动态的平均升力系数和动态平均力矩系数越大,频率较高时的失速迎角相对于频率较低时的情况有所推迟,但相对于静态的失速迎角而言,不同频率下的动态失速迎角均提前。对于沉浮运动而言,动态平均升力系数随振幅和频率的增加而减小,动态失速迎角随振幅和频率的增大而提前。
By solving the Reynolds averaged unsteady Navier-Stokes equations, the numerical simulation method is used to calculate the effect of pitch and sway vibration on the average aerodynamic characteristics of NACA0012 airfoil. The results show that for the pitch motion, the influence of the variation of the amplitude angle on the dynamic average lift coefficient and the dynamic average moment coefficient is not obvious in the linear section of the lift and moment curves when the angle of attack α ≤ 13 °, When the angle of attack is α≥14 °, the average lift coefficient and dynamic average moment coefficient of airfoil vibration are smaller than those under static condition. The higher the pitch vibration frequency under the same angle of attack, the larger the dynamic average lift coefficient and dynamic average moment coefficient, while the higher the frequency, the stall attack angle is delayed than the lower frequency. However, In terms of static stalling angle of attack, the dynamic stall angles of attack at different frequencies are advanced. For the ups and downs, the dynamic average lift coefficient decreases with the increase of amplitude and frequency, and the dynamic stall angle of attack advances with the increase of amplitude and frequency.