Weight reduction of 3D-printed cylindrical and toroidal pressure vessels through shape modification

Considerable weight savings can be provided by metal additive manufacturing through geometries that are impossible or very difficult to produce by conventional methods. The paper demonstrates it on two classes of pressure vessels: Baseline configurations of a domed cylinder and a simple torus that evolve through repeated design-and-analysis cycles. Each iteration of intuitive geometrical change results from the previous finite-element stress analysis until converging to a final design that exhibits largely uniform stress levels throughout the inside surface of the vessel and relatively high stresses elsewhere. Weight savings of ~26% are obtained with a “peanut” shaped vessel compared to its domed cylindrical counterpart, and ~63% for an asymmetrical torus compared to the symmetrical baseline, both while keeping the internal volume, pressure and allowable stress the same.