Numerical investigation of non-planarity and relative motion for bionic slotted wings

Bird wings have split primary feathers that extend out from the wing surface. This structure is called wingtip slot, which recognized as a product of bird evolution to improve flight performance. In this paper, numerical simulations based on RANS (Reynolds-averaged Navier–Stokes) equations are conducted examine and understand influence slots six at Re = 100 000. The overlapping grid method, driven by an in-house UDF (User Defined Function), used model motion bionic slotted wings. law winglets improved extracted level-flying bald eagle. Then aerodynamic force, pressure distribution, vorticity contours, wake stream, other flow structures with different layouts were compared analyzed. results show significant increase in force when wingtips employed. maximum lift-to-drag ratio also our designed non-planar 34% base wing. Each winglet works single due existence slots, chordwise distribution similar main vortex expressive changes tip Additionally, innovative proposed dynamic forms varying gaps between winglets. Due collective mechanism interaction among multiple for wing, it acquires optimal time-averaged during flapping period. As expected, reduces intensity creates weaker vortices. non-planarity relative strengthen its weakening effect wake.