Multi objective optimization of sound transmission across laminated composite cylindrical shell lined with porous core investigating Non-dominated Sorting Genetic Algorithm

The current formulation applies Non-dominated Sorting Genetic Algorithm (NSGA-II) as well as First-order Shear Deformation Theory (FSDT) to optimize Sound Transmission Loss (STL) of the laminated composite cylindrical shell lined with a porous material subjected to a plane sound wave. Therefore, in the first part of the paper, the Extended Full method [29] is employed to provide an exact solution based on three dimensional elasticity theory as well as investigating the well-known Helmholtz decomposition to present fluid pressure, the displacement fields and the solid stresses. Subsequently, some configurations are brought up to illustrate the accuracy of the present results. Furthermore, this paper also clarifies the importance of applying porous layer by demonstrating the direct influence between porous layer thicknesses and STL of the structure particularly in high frequency region. Consequently, in the second part of the paper the NSGA-II method is applied to multi objective optimize of sound transmission into such structure taking account the appropriate Pareto front which result in substantial improvement on the performance of the system based on minimizing the weight as well as maximizing sound transmission. Therefore, this procedure is followed by considering suitable design variables to designate what combination of design variables could result in a composite shell satisfying the sound insulation.