OPTIMIZATION OF DESIGN PARAMETERS OF THE MAIN COMPOSITE FAIRING OF THE LAUNCH VEHICLE UNDER SIMULTANEOUS FORCE AND THERMAL LOADING

Main aspects of multi-stage optimization of the mass of main structural elements of launch vehicle's composite protective fairing under the simultaneous thermal and force loading are outlined. The technique is implemented within the integrated approach to the integrated design of the considered class of engineering proposed earlier. The obtained results allow a deep level of simultaneous optimization of thermal protection thickness, layout and arrangement of bearing skins, the height of honeycomb core and geometric parameters of its cell, as well as additional structural parameters for the almost entire range of external loads affecting the protective fairing. At the same time, the allowable temperature ranges of outer and inner surfaces of the considered unit are provided, as well as its rational design's bearing capacity in all critical areas, taking into account the heat-caused deterioration of physical and mechanical properties of materials used and the implementation of additional functional and technological constraints. Implementation of the proposed methodology for optimizing the structural parameters of a particular real product - the protective fairing of the "Cyclone-4" launch vehicle - revealed its effectiveness expressed in a significant reduction in mass of the optimal design compared to the original one.