Efficacy of Active Flow Control in Suppression of Wing Rock in Blended-Wing–Body Configurations

Blended-wing–body (BWB) has emerged as a potential concept to replace the traditional tube and wing (TAW) configuration. As with traditional flying wings, the BWB is prone to the wing-rock phenomenon but with a different triggering mechanism, which causes significant flight stability and control challenges. This paper aims to investigate the wing-rock characteristics of a BWB unmanned combat aerial vehicle and further evaluate the efficacy of active flow control techniques for its suppression. A validated computational framework has been developed based on rigid-body single-degree-of-freedom (single-DOF) dynamic mesh motion and forced roll sliding mesh motion employing the unsteady Reynolds-averaged Navier–Stokes equations. Free-to-roll simulations have predicted the onset angle of attack and various wing-rock characteristics. Jet blowing was influential in suppressing wing-rock amplitude and mean roll angles within a specific range of angles of attack, after which its momentum coefficient has to be increased. Liutex-based flow analysis revealed complex tip-separated flow interactions and the coalescence of multiple vortex systems as the primary causes of wing-rock initiation. The developed framework can be extended to multi-DOF analyses, flow-adaptive blowing, or to investigate other dynamic instabilities.