Vortex Flow Control Over a Delta Wing By Co-Rotating and Counter-Rotating Vortex Generator

Abstract

A conventional double-delta or strake-delta wing generates a co-rotating vortex pair; one from the strake and the other from the main delta wing, which goes through a merging process, creating one strong vortex system core over the main wing. The merging process gives beneficial effects as it stabilizes the main wing vortex and produces higher suction lift. However, it tends to break down at wing aft region due to the higher rotational velocity of the merged vortex. This paper investigates the effects of a counter-rotating vortex pair on the aerodynamic characteristics of a strake-delta wing configuration. A new concept of a variable geometry strake (VGS) which can generate combinations of co-rotating and counter-rotating vortex pairs is implemented and its feasibility to be used as an active flow control actuator is tested through CFD simulations. The results indicate that a counterrotating vortex pair can greatly alter the aerodynamic forces on a delta wing beyond 20 o AOA. At 28 o AOA, the lift coefficient for a VGS configuration is improved by 22.4% over a conventional strake-delta case.