Active suction control for supersonic crossflow instability on finite-span swept wings with sensitivity analysis

A physics-based framework for active control of supersonic crossflow instability on finite-span swept wings is developed using global stability and adjoint-based sensitivity analysis. The approach identifies the wavemaker region—the flow domain most sensitive to feedback forcings—through structural sensitivity analysis of the dominant crossflow mode. Numerical simulations demonstrate that suction control applied within this wavemaker region achieves superior crossflow instability suppression compared to alternative chordwise locations. The control effectiveness shows a strong dependence on suction intensity, with moderate suction yielding significant N-factor reduction and improved spanwise uniformity of disturbance growth. Global stability analysis demonstrates that the control implementation substantially reduces spatial growth rates, induces downstream migration of the instability components, and can generate dual wavemaker regions. These findings elucidate the physical mechanisms for engineering control strategies and establish sensitivity analysis as an effective tool for designing efficient active control systems.