Vibro-acoustic analysis of double-walled cylindrical shells through a novel semi-analytic method

• Published in: European journal of mechanics, A, Solids Vol. 94; p. 104559
• Main Authors: Xie, Kun, Jia, Wenchao, Dong, Wanjing, Chen, Meixia
• Format: Journal Article
• Language: English
• Published: Berlin Elsevier Masson SAS 01.07.2022; Elsevier BV
• Subjects: Acoustics; Annular plates; Boundary conditions; Boundary element method; Conical shells; Continuity (mathematics); Cylindrical shells; Double-walled cylindrical shells; Finite element method; Fourier series; Helmholtz integral equation; Integral equations; Mathematical analysis; Mathematical models; Power series; Segments; Semi-analytic method; Shell theory; Shells; Sound pressure; Structural models; Vibro-acoustic analysis; Vibroacoustics; Vibro-acoustic analysis; Conical shells; Helmholtz integral equation; Semi-analytic method; Double-walled cylindrical shells
• DOI: 10.1016/j.euromechsol.2022.104559
• ISSN: 0997-7538

A novel semi-analytic model is developed for vibro-acoustic analysis of immersed double-walled cylindrical shells coupled by annular plates and annular fluid between two shells. For structural model, it is firstly divided to inner shell, outer shell and annular plates, and the inner and outer shells are further divided to narrow shell segments. By utilizing Flügge shell theory and power series method, all shell segments and annular plates are uniformly analyzed as conical shells, and they are rapidly assembled to the overall structural model via boundary conditions and continuity conditions between segments. For acoustic model, interior annular fluid region and exterior infinite fluid region are separately analyzed via the Helmholtz surface integral equation. Two surface integrals are simplified to two line integrals after expanding surface sound pressure and velocity as Fourier series, so the pressure is further expressed as displacements of all segments. Through adding the pressure to the continuity conditions, the structural model is coupled with acoustic model. High efficiency and accuracy are demonstrated via comparing vibro-acoustic results of present method with ones in the literature or calculated by coupled finite element-boundary element method. Furthermore, effects of annular plates, annular fluid and excitation on vibro-acoustics of double-walled shells are discussed. •A novel semi-analytic model for vibro-acoustics of submerged double-walled cylindrical shells.•The developed model is of wide application, rapid convergence and high accuracy.•Increasing annular plates obviously suppresses vibrations and slightly affects sound power.•Effects of annular fluid become slight as annular plates increase.