VORTEX FLOW-CONTROL USING FILLETS ON A DOUBLE-DELTA WING

This article presents results from a subsonic numerical investigation on the effects of geometry modifications at the junction of the leadin g edge extension (LEX) and wing of a flat-plate cropped double-delta w ing at moderate to high angles of attack. The baseline planform of the double-delta wing configuration consisted of a strake with a 76-deg l eading-edge sweep and a wing with a 40-deg leading-edge sweep with sha rp, beveled leading edges. The geometry modifications included various fillet shapes with planform areas equal to 1% of the baseline wing re ference area. A hyperbolic grid generation method was developed and us ed in conjunction with an existing interactive grid generation system to create high quality C-O type multiblock grids about the configurati ons studied. The Euler and Reynolds averaged Navier-Stokes (RANS) equa tions were solved numerically using two finite-volume production flow solvers. The baseline configuration numerical results correlated well with existing published experimental data. Grid refinement using the R ANS revealed vortex sheet tearing on the wing. Fillets enhanced the li ft by 14% at low angle of attack, and 18% at high angle of attack with a slight improvement in lift-to-drag ratio. The fillets may be good c andidates for roll control devices.