Vibration and Sound Radiation of Flexibly Supported Circular Laminated Composite Plates
|關鍵字:||振動;複合材料;聲傳;圓板;彈性支撐;聲壓位準;vibration;composite;sound radiation;circular plate;flexible suspension;sound pressure level|
Vibration characteristics and sound radiation of flexibly supported circular laminated composite plates are studied in this thesis. Using both theoretical and experimental means, we investigate how layer angles and laminated composite structure affect the sound radiation of the flexibly supported circular plates. The effects of continuous and discontinuous flexible suspensions on the SPL of the same circular plates were studied. The flexible suspension using PU foam was formed through a process of heating and pressing and the stiffness of the suspension was measured from experiments. In analysis, elastic springs were used to simulate the flexible suspensions. The dynamic behaviors of the circular laminated composite plates and circular sandwich plates were studied based on the Classical Laminated Plate Theory or the First Order Shear Deformation Theory, and the Ritz method was used with a power series as the displacement function to yield natural frequencies and natural models of the circular plates. In the part of SPL calculation, we established the models of the circular composite plates using ANSYS for harmonic response analysis. And then we used the calculated amplitude and phase of each element in the circular plate to construct the SPL spectrum. Furthermore, the effects of different variables, such as lamination angle, plate thickness, stiffness of springs on the trend of the SPL curves were also studied. In the experimental study, we made circular composite laminated plates and sandwich plates. And then we proved that the solutions of theoretical analysis were consistent with the experimental results of SPL and natural frequencies. The results provided in this thesis may be of value for designing circular radiating panels having efficient radiation capability.
|Appears in Collections:||Thesis|