利用离散涡方法对俯仰振荡翼型诱导出的非定常流场进行了数值模拟.针对以往离散涡方法无法精确计算前缘涡脱落的问题,利用边界层涡量和分离点处脱落涡量的关系,推导出了高攻角情况下前缘涡脱落位置以及环量的计算公式.分析了高低两种攻角振幅对应的前缘涡和尾缘涡的生长以及脱落过程,结合流场对翼型所受升力的演化过程进行了定量化研究.结果表明,振荡的攻角幅值越大,升力极值越大,由于前缘涡脱落导致的升力下降的程度愈加剧烈.%The unsteady flow field induced by the pitching airfoil is numerically simulated.Aiming at the problem that the discrete vortex method can not accurately calculate the shedding process of the leading edge vortex in the past,the solving formulations of the location and circulation of leading edge vortex are deduced by using the relationship between the boundary vorticity and the vorticity at the separation point.The growth and detachment processes of the leading vortex and trailing edge vortex are analyzed.The evolution of the lift generation process is quantitatively studied based on the flow field.The results show that the larger the amplitude of the angle is,the greater the lift value is,and the degree of lift decrease is more intense due to the leading edge vortex shedding.
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