Effects of end plates on vibro-acoustic responses of conical and cylindrical shells

Abstract

A unified semi-analytic model is developed to study effects of end plates on vibro-acoustic characteristics of conical and cylindrical shells. The Flügge shell theory and power series method are combined to establish the structural model, while the boundary integral method for acoustic problems of axisymmetric bodies is employed to develop the acoustic model. By utilizing continuity conditions between structural and acoustic models, the vibro-acoustic governing equation is readily achieved. Rapid convergence of the developed model is discussed, and high accuracy and efficiency of present method are verified with the ones in the literature and calculated by finite element-boundary element method. Furthermore, the coupling effect between end plates and external fluid, contributions of end plates to vibro-acoustic responses and the effect of thickness of end plates are discussed. Results reveal that the coupling effect between end plates and external fluid is remarkable for cylindrical shells under axial forces or conical shells under both axial and radial forces. Simultaneously, contributions of end plates to vibro-acoustic responses are significant, and the variation of thickness of end plates apparently affects vibro-acoustic responses of the closed conical and cylindrical shells.