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arXiv · 1403.6824

A study on aerodynamics and mechanisms of elementary morphing models for flapping wing in bat forward flight

Guan Zi-Wu·Yu Yong-Liang
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Abstract

The large active wing deformation is a significant way to generate high aerodynamic forces required in bat flapping flight. Besides the twisting, the elementary morphing models of a bat wing are proposed, such as wing-bending in the spanwise direction, wing-cambering in the chordwise direction, and wing area-changing. A plate of aspect ratio 3 is used to model a bat wing and a three dimensional unsteady panel method is applied to predict the aerodynamic forces. It is found that the cambering model has a great positive influence on the lift, followed by area-changing model and then the bending model. The further study indicates that the vortex control is a main mechanism to produce high aerodynamic forces, and the mechanisms for the aerodynamic force enhancement are the asymmetry of the cambered wing and the amplifier effects of wing area-changing and wing bending. The lift and thrust are mainly generated during the downstroke and almost negligible forces during the upstroke by the integrated morphing model-wing.

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Guan Zi-Wu, Yu Yong-Liang. 2014-03-27. A study on aerodynamics and mechanisms of elementary morphing models for flapping wing in bat forward flight. https://doi.org/10.1007/s10483-015-1931-7

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