Abstract
Micro air vehicles and vertical-takeoff-and-landing drones usually operate at relatively low values of the Reynolds number (). In the present study, three airfoils from different categories (AG14, BE50, and SD7032) are studied at . How the behavior of the laminar separation bubble changes with the Reynolds number is investigated and is found to give rise to differing aerodynamic forces that can severely degrade the aerodynamic performance of low-Reynolds-number airfoils. To obtain airfoils with satisfactory aerodynamic performance over a wide range of low Reynolds number, a multi-objective optimization approach is proposed and implemented with different design considerations. The airfoils optimized at these Reynolds numbers have a geometric dimple, as confirmed by unsteady Reynolds-averaged Navier–Stokes simulations with a transition model, and by particle image velocimetry wind-tunnel testing. The dimple is effective in restricting the location and size of the laminar separation bubble, leading to robust and significantly improved aerodynamic performance. Also studied is how the number of nonuniform rational B-spline control points affects the optimum airfoil results, and the dimple always appears in the optimum geometry for .
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
