Suppression of Flow-Induced Vibration Using Reinforced Structures from Spatial/Wave-Number Domain

Flow-induced vibration is a major contributor to structural damage in aircraft. This work aims to mitigate such vibrations using reinforced structures. Unlike conventional reinforcement approaches, the structures developed here are engineered to align the aerodynamic mode with the structural mode in the spatial/wave-number domain, thereby minimizing flow-induced vibration. To achieve this, a multi-iteration design method is first introduced to reduce structural vibration by tuning the structural natural frequencies through adjusting stiffener dimensions so that the structural mode approaches the minimum-vibration condition under a given wall-pressure excitation. However, the optimal reinforcement scheme is difficult to obtain within a limited number of iterations. To further enhance the efficiency of reinforcement design, an improved method is developed that accelerates the design process by directly determining reinforcement dimensions using generated velocity contours for certain wall-pressure fluctuation modes. Evaluation of the vibration-suppression performance indicates that the newly developed methods significantly reduce flow-induced vibration and effectively control structural stress at the natural frequency as compared with conventional reinforcement strategies.