Vibration Suppression of Stiffened Laminated Composite Panels with Variable Angle Tow Fibers

The vibration energy flow characteristics of stiffened laminated composite (SLC) panels with variable angle tow (VAT) fibers subjected to a harmonic excitation force was investigated. A finite element (FE) model was established for the free and forced vibration analysis of SLC panels and validated via comparisons with results from the literature. The power flow analysis of SLC panels with various layups was carried out. A FE-based power flow analysis was conducted to show input power, energy transmission and distribution patterns on the various SLC panels. The vectors of power flow density explicitly exhibit the detailed paths of vibration energy flow within the plate with single and double stiffeners. The influences of the thickness, number, and position of the stiffeners as well as the fiber angles of the stiffener and plates on energy transfer were investigated. It was shown that the stiffeners exert significant impact on energy transmission paths. Effectiveness of using VAT skins for vibration energy flow tailoring was demonstrated. An enhanced understanding of the energy flow behavior of SLC panels was obtained, providing benefits to the vibration suppression of stiffened composite structures by designing stiffeners and VAT skins.