采用简化的几何模型模拟蝙蝠翼的形态和变形挥拍，用计算流体力学方法研究仿蝙蝠翼变形挥拍的气动力特性。建立平行四边形的内翼和三角形组合的外翼模型，翼的变形分为面积变化、外翼弯曲、弓形变形和翼面扭转4类，并根据实验数据设定慢速飞行和快速飞行2种运动模式。结果表明，在慢速和快速2种飞行模式下，模型蝙蝠翼气动力的时间变化和空间分布是相似的，升力和推力均在下拍过程产生，而上挥过程的气动力均较小。推力完全依靠外翼产生，而升力则由外翼和内翼共同产生。进一步分析表明，慢速模式适应低速飞行，主要依靠调节攻角适应不同的飞行速度，频率在较小范围改变即可；快速模式适应快速飞行，主要依靠调节挥拍频率满足不同速度下的气动力平衡，攻角的调节范围较小。
A simplified geometric model of a bat wing was utilized to study its morphology and deformation, along with its aerodynamic characteristics, using computational fluid dynamics methods. A model was established with a parallelogram-shaped inner wing and a combined triangular outer wing. The wing deformations were categorized into four types:area variation, outer wing bending, chordwise cambering, and wing twisting. Two flight modes, slow and fast, were defined based on experimental data. The results demonstrate that the aerodynamic forces acting on the bat wing model in both slow and fast flight modes are similar in spatial-temporal distribution, with both lift and thrust generated during the downstroke phase. The forces during the upstroke phase are comparatively smaller. Thrust is generated entirely by the outer wing, whereas lift is generated by both the outer and the inner wings. Furthermore, it was found that slow flight achieves velocity adaptation primarily through angle-of-attack adjustments, supplemented by minor flapping frequency modulation. In contrast, fast flight relies predominantly on frequency adjustments, with fine-tuning of the angle of attack to maintain force equilibrium across different speeds. The analysis of the aerodynamic forces acting on the deforming bat wing contributes to a more profound comprehension of the mysteries of bat flight.
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