Vibro-Acoustic Optimization of Turbulent Boundary Layer Excited Panel with Curvilinear Stiffeners

Abstract

The present work addresses the structural-acoustic design optimization study of straight or curvilinearly stiffened panels excited by turbulent boundary layer (TBL) pressure fluctuation. The Corcos model of representing TBL is used to capture the correlation of TBL pressure excitation. Validation of the Corcos TBL model, implemented in a framework, named EBF3PanelOpt, is also performed. For a comparative study, two optimal baseline designs are obtained for a panel with two and four stiffeners, respectively. The optimal designs obtained by performing acoustic optimization have reduced the maximummean square pressure radiated in the far field by 11.4 dB for a panel with two stiffeners and 18.5 dB for a panel with four stiffeners. The reduction of mass and the acoustic response during structural-acoustic optimization are conflicting in nature. Therefore, amulti-objective design optimization using the nondominated sorting genetic algorithm-II (NSGA-II) in VisualDoc is performed. The best Pareto-optimal design with four stiffeners, obtained using the multi-objective design optimization approach, has reduced the maximum mean square pressure radiated in the far field by 4.8 dBwhen comparedwith the baseline designwith four stiffeners. The obtained optimal designs meet all of the constraints, such as buckling eigenvalue, von Mises, and crippling stresses.