运用双时间推进法和动态嵌套网格技术对扰动风作用下的多段翼型非定常绕流进行了数值模拟. 首先, 结合预处理技术对麻省理工学院(Massachusetts Institude of Technology, MIT) 的翼型模型在扰动风作用下的流动进行数值模拟, 并运用其实验结果验证程序的正确性; 然后, 对多段翼型在周期性的扰动风作用下的非定常粘性绕流进行数值模拟, 得到非定常情况下气动力随扰动风变化的迟滞规律. 计算范围内的结果表明: 扰动风的频率越低, 幅度越大, 多段翼型整体上的气动力越大; 扰动风的频率越高, 幅值越大, 对多段翼型的气动力影响越大.
Dual-time step method and moving overset grid method are applied to simulate the multi-element airfoil. First, combined with preconditioning method, the flapping foil experiment of MIT (Massachusetts Institude of Technology) is simulated to validated the numerical method. A multi-element foil under the effect of gusts is simulated to give the disciplines of the aerodynamic forces changing with the phases of gusts. Simulated results shows that, the lower the frequency and the larger the amplitude of the gust, the larger the aerodynamic forces on the multi-element airfoils. On the other hand, the higher the frequency and the larger the amplitude of the gust, the more intense the gust will affect the aerodynamic forces on the multi-element airfoils.
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