Development of a new method for design of stiffened composite pressure vessels using lattice structures

Abstract

A new method to design composite pressure vessels under strain and strength constraints using lattice structures is described. A graphical analysis is presented to find the optimum geometrical parameters of the rib for given fiber orientations. Minimum pressure vessel mass is determined from active execution of two constraints. Composite lattice structures are suggested as a new way of strain suppression among the commonly used methods such as (1) addition of extra plies, (2) use of composite material with a higher stiffness and (3) replacement of the circumferential layer with a second helical layer made of different materials. The experimental and analytical results of application of the method indicate that the vessel covered with composite lattice structures presented considerable weight savings with respect to traditional stiffened vessels.