Aerodynamic Performance of an Unmanned Aerial Vehicle Wing For Varied Wing Geometric Parameters

Abstract

The aerodynamic performance characteristics of a small unmanned aerial vehicle wing are evaluated computationally at a moderate Reynolds number of Re = 2.8 x 105. The flow exhibits laminar-turbulent transition and features a laminar separation bubble that exists for a substantial portion of the wing span. The flow near the wing tip is three-dimensional and exhibits complex flow patterns due to the interaction of the wing tip vortex with the laminar separation bubble. A series of systematic parametric studies are conducted by varying the wing geometric parameters like the span of the rectangular inboard wing, sweep of the outboard wing and wing dihedral angle. From the parametric studies, it is found that the wing with an outboard sweep of 17° has a 4.54 % improvement in endurance factor compared to the baseline wing at an angle of attack of 5°. The drag of this wing is 19.2 drag counts lower compared to the baseline wing. Further, flow transition is delayed for this wing. The present results show that wing sweep has a significant influence on the improvement of aerodynamic performance of unmanned aerial vehicle wings at moderate Reynolds numbers.