Aerodynamic mechanism of forces generated by twisting model-wing in bat flapping flight

• Published in: Applied mathematics and mechanics Vol. 35; no. 12; pp. 1607 - 1618
• Main Author: 管子武 余永亮
• Format: Journal Article
• Language: English
• Published: Heidelberg Shanghai University 01.12.2014
• Subjects: Aerodynamics; Applications of Mathematics; Bats; Classical Mechanics; Drag; Flapping wings; Fluid- and Aerodynamics; Lift; Mathematical Modeling and Industrial Mathematics; Mathematical models; Mathematics; Mathematics and Statistics; Partial Differential Equations; Three dimensional; Twisting; Wings (aircraft); 动力学机理; 扑翼; 扭动; 昆虫飞行; 机制; 模型; 空气动力; 蝙蝠; O355; O351.2; 76B47; panel method; bat wing; 76Z10; twisting; aerodynamic mechanism; 76M23
• ISSN: 0253-4827; 1573-2754
• DOI: 10.1007/s10483-014-1882-6

The aerodynamic mechanism of the bat wing membrane Mong the lateral border of its body is studied. The twist-morphing that alters the angle of attack （AOA） along the span-wise direction is observed widely during bat flapping flight. An assumption is made that the linearly distributed AOA is along the span-wise direction. The plate with the aspect ratio of 3 is used to model a bat wing. A three-dimensional （3D） unsteady panel method is used to predict the aerodynamic forces generated by the flapping plate with leading edge separation. It is found that, relative to the rigid wing flapping, twisting motion can increase the averaged lift by as much as 25% and produce thrust instead of drag. Furthermore, the aerodynamic forces （lift/drag） generated by a twisting plate-wing are similar to those of a pitching rigid-wing, meaning that the twisting in bat flight has the same function as the supination/pronation motion in insect flight.