Abstract:
Flapping wing micro aerial vehicles are studied as the substitute for fixed and rotary wing micro
aerial vehicles because of the advantages such as agility, maneuverability and employability in
confined environments. Hummingbird’s sustainable hovering capability inspires many researchers
to develop MAVs with similar dynamics. But in previous studies, either kinematics or wing shape
of the hummingbird is changed. In this study, a wing of a ruby-throated hummingbird is modeled
as an insect wing using a membrane with curved leading-edge stiffeners and straight surface
stiffeners. The same shape and kinematics are used for the design. The effect of flexibility on the
aerodynamic performance of a wing at hovering flight has been studied numerically by using a
Fluid-Structure Interaction scheme at a characteristics Reynolds Number of 3000. The
computational model is validated by experimental results selected from the literature. Different
wings have been developed by using the different position and thickness of the surface stiffener.
The chord and span-wise flexural stiffness of designed wings match well of the insects of the same
size. A rigid wing is designed, and its analysis is performed to compare the aerodynamic
performance with the flexible wing. In the case of different stiffener positions, the best performing
wing has an average lift coefficient of 0.51. In addition, in the case stiffener thickness, the best
performing wing has an average lift coefficient of 0.56. In comparison with the average lift
coefficient of 0.48 for the rigid wing and 0.61 for the ruby-throated hummingbird wing, the highest
lift coefficient of 0.56 was obtained by the flexible wing modelled in this work. The results show
that flexibility has positive effect on the lift production of hummingbird-like wing in hover. It was
also been found that flexible wing can support the weight of a modelled bird of 3.4 grams.
