Investigation of non-regular grids for lattice fuselage barrels

The results of strength and weight efficiency analysis of composite fuselage sections with lattice structure layouts are presented. A rational nonregular layout of the lattice grid is proposed, which has an enhanced weight efficiency in comparison with the regular (periodic, along the length of the fuselage) one. The rational non-regular grid layout is formed by changing the geodesic direction of the spiral ribs with a constant angle of orientation to the longitudinal axis of the fuselage for a curvilinear direction of the spiral ribs. The validation of the proposed lattice grid layout was carried out using an automated parametric method for FEM strength analysis of lattice composite barrels. As objects of investigation, a number of barrels of an elongated fuselage structure of a perspective passenger aircraft were selected, having a diameter of 4m and lengths from 6 to 10 m. The weight effectiveness of the proposed layout was shown.