中文摘要：

通过动态混合网格技术和基于虚拟压缩方法的不可压缩流非定常计算方法，对“合拢-打开”（clap-fling）机制下小型昆虫翼的周期性运动进行了数值模拟，并与单个翼拍动时的升力系数、流场结构进行了对比分析，同时对比研究了雷诺数对力学特性、流场结构的影响，探讨了“clap-fling”机制能够增强升力的流动机理。对比发现，“clap-fling”机制增升的关键在于合拢-打开过程中的三个升力峰值以及之后平动阶段的“不失速机制”；且当雷诺数较小时，“clap-fling”机制增升效果最为明显。

英文摘要：

While analyzing the hovering motion of the tiny wasp Enearsaria formosa, Weis-Fogh proposed a novel aerodynamic mechanism that enhanced lift during flight, known as the ＂clap-fling＂ mechanism. Based on the dynamic hybrid mesh generator and the unsteady incompressible solver developed by the authors before, the ＂clap-fling＂ motion as well as the flapping motion of a single wing are studied numerically in this paper. By comparing the flow structures and the lift/drag characteristics, the mechanism of lift-enhancing with ＂clap-fling＂ motion as well as the influence of the Reynolds number are analyzed.