Wind tunnel investigation into the bio-inspired slotted winglets for micro air vehicles

The reported study investigates the effect of slotted winglet configurations on the performance of low aspect ratio ( AR ) wings meant for micro air vehicles (MAVs). The inspiration of this slotted winglets is derived from the primary feathers of soaring bird wings. This bio-inspired approach is used to replicate the aerodynamic benefits of the MAV wings. In view of this, the present study is conducted on S5010 profiled wing at two AR s in the presence of wingtip attachments. The wind tunnel experiments involve two shapes of wingtip attachments, viz., tapered and conical forming the slotted winglet configurations. The aerodynamic parameters such as lift, drag, induced drag, lift-to-drag ratio and pitching moment are evaluated in the range of low Reynolds number ( Re ). The tapered slotted winglets demonstrate superior performance as compared to the base wing of the same AR . Further, there is a decrease of induced drag with the higher number of attachments. It has also been observed that with an increase in Re , the performance of winglet configurations improves significantly.