Selection and optimization of polymer composite load-bearing elements parameters in structurally optimized designs

Modern development of aircraft and aerospace structures is aimed at increasing weight and structural efficiency while simultaneously meeting requirements for strength, stability, aeroelasticity, and manufacturability. In recent decades, structures with curved load-bearing elements, directional fiber orientation in composite layers, and bio-inspired structures, which significantly outperform traditional rectilinear designs, have been actively studied. This paper compares structurally optimized structures with traditional reinforcement schemes. The object of study is the shape (planform view) of ribs for a polymer composite square plate. Three types of reinforcement elements and their number are considered: rectilinear, single-curvature (C-shape), and double-curvature (S-shape). The options were evaluated based on the results of an assessment of the stress-strain state, stability, and mass of the structure. The advantages of single-curvature and double-curvature ribs over rectilinear ones were established. The results of this work are part of a comprehensive study of promising structurally optimized structures made of polymer composite materials.
EDN: CXSDZE, https://elibrary/cxsdze

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