Numerical simulation and constructal design applied to biaxial elastic buckling of plates of composite material used in naval structures.

• Constructal Design is effective to improve the perforated composite plate's mechanical behavior. • The best mechanical behavior of cross-ply lamination includes angles of 45°. • The maximum buckling load for each volume fraction occurs when the elliptical geometry is longer on y-axis. Thin plates when subjected to compressive loads can present a structural instability phenomenon known as buckling, causing displacements out of the plane of the plate. In addition, it is known that the use of composite materials in naval engineering can bring many benefits in the medium and long term, like the major corrosion resistance, when compared with steel structures. Moreover, for specific applications perforated plates are necessary, like passage of cables and pipes, inspection windows, among others. Therefore, to find the optimal geometry of a composite plate with a centered elliptical hole the Constructal Design (CD) was applied in association with the Exhaustive Search (ES) technique and Finite Element Method (FEM). The CD allows the evaluation of the geometry that provides the optimal distribution of imperfections, leading to the maximum value of the performance parameter used for the analysis of solids mechanics problems. Applying different laminations, it was observed an increase in the critical buckling load for a composite plate without perforations of up to 10.47%. In its turn, despite suffering a reduction in the critical load value if compared to the plate without holes, an improvement of 16.89% was observed when optimal and worst geometries for the perforated plates are compared. [ABSTRACT FROM AUTHOR]