Aeroacoustic Optimizations of Internal Bay Cavity Flow Control Devices

Minimizing radar cross section in stealth aircraft requires internal weapon bays, which introduce strong aeroacoustic resonance driven by shear-layer–acoustic feedback. However, existing cavity flow control studies typically treat leading-edge and trailing-edge modifications independently, with limited consideration of their coupled interaction in controlling the feedback mechanism. This study investigates a coupled passive flow control configuration consisting of a leading-edge inclined ramp and a trailing-edge slanted wall for noise suppression in cavity flows. The design is optimized using a combination of Taguchi-based parameter exploration and gradient-based refinement, with performance evaluated through computational fluid dynamics simulations validated against wind tunnel measurements. The optimal configuration (A1B3C2D1) reduces the average overall sound pressure level from 161.63 to 155.81 dB (5.82 dB). The leading-edge inclined height (factor A) is identified as the dominant parameter, primarily influencing shear-layer behavior and reducing energy transfer into the cavity. These results demonstrate the effectiveness of coupled geometric modifications for aeroacoustic control and provide a physically grounded basis for passive noise suppression strategies in internal bay applications.