Multivariable numerical optimisation and parametric study for a new kick-stage space vehicle for LEO applications

This research article presents a numerical optimisation and parametric study regarding the design process of a new innovative kick-stage component for aerospace applications. Given the intense rush for space -related services and its expected growth over the next few years, more dedicated rockets capable of delivering small satellites into their desired orbits are becoming increasingly popular. Modern design practices of globally elastic and locally plastic structures are commonly used in solutions nowadays. Aligned with more complex shapes of mechanical components, they play a crucial role in optimising mass and volume. During the last few years, aerospace structures have evolved from metal structures to laminated composite and/or sandwich-based ones because of the advantages regarding strength, stiffness -to-density ratios, flexibility, and durability, just to mention a few. This study presents a comprehensive analysis involving the conceptualisation, testing, optimisation, and design of a kick-stage structure using aluminium-based and composite-based models while illustrating how multivariable studies can be used after optimisation analysis to reach a manufacturable and efficient design. Several specimens were analysed to capture their frequency response and eigenmodes, indicating that without proper reinforcement, the structure does not have enough stiffness and structural performance to handle the frequency limits required and is not suitable to the space and vibration environment that will be subjected to. Based on the outputs obtained and by comparing different solutions, the composite-based model that comprises a honeycomb sandwich structure emphasises advantages regarding mass and frequency response. Nevertheless, the study also explores in depth the influence of other design variables on the performance of the space structure such as the thickness and density of the aluminium ribs, thickness of the plates, geometric configuration of the elements, number of carbon plies, and thickness of the core, among others. The conclusions from this study will ultimately be used to decide which option will be selected as the final approach for the design.(c) 2023 Elsevier Masson SAS. All rights reserved.