Three-dimensional Reynolds averaged Navier-Strokes numerical simulations were carried out to predict the flow field characteristics of a 76° swept delta wing undergoing a pitch motion at high angle of attack. The Baldwin-Lomax eddy viscosity model with the modifications suggested by Degani and Schiff was used here. Three cases were considered to investigate the frequency effect on the aerodynamic loads for the delta wing. And the unsteady aerodynamic loads for the delta wing which oscillate at different range of angle of attack are also shown in the paper. It is concluded that the aerodynamic loads show a hysteresis circle when the delta wing oscillates in pitching, and the hysteresis phenomenon is more distinct when the frequency becomes faster. The hysteresis circles are changed clearly when the delta wing oscillates at large range of angle of attack.%应用有限体积方法求解三维可压缩雷诺平均N-S方程,对76° 后掠角三角翼作大迎角俯仰运动时的动态气动力系数进行计算,研究三角翼以不同频率进行大迎角俯仰振动和在不同迎角范围内进行俯仰振动的非定常气动力系数变化特征,对减缩频率和振动所在的迎角范围对三角翼动态非定常气动力迟滞特性的影响进行分析.计算结果表明,在三角翼作大迎角俯仰谐振荡过程中,升力、阻力和俯仰力矩系数曲线都形成明显的滞环,且随着减缩频率增加,所产生的迟滞特性明显增强;在同一减缩频率下,三角翼在较大迎角范围内作周期振动时,所表现的迟滞特性明显不同.
展开▼
