Optimal Design of Composite Shelled Sandwich Structures with a Honeycomb Filler

Abstract

The multi-parameter problem of the optimal design of composite sandwich structures with the honeycomb filler has been solved. For this purpose, the optimization process was divided into several stages according to the reasonable levels of significance of the objective function’s parameters, i.e., minimal weight. At the first stage, preliminary analysis of thermal protection coatings of sandwich structures with the honeycomb filler is carried out, the most rational types thereof are found, the values of physical and mechanical characteristics, as well as the optimal ranges of variation and the initial value of the thickness of thermal protection coatings for different sections of the structure, are determined. At the second stage, the task of choosing the optimal relationship of the thickness of the thermal protection coating, height of the honeycomb filler, size of its cell, and thicknesses of bearing skins is solved, with simultaneous securing of the acceptable temperature ranges for the outer and inner surfaces of sandwich shells and bearing capacity of the rational variant in all critical areas. To further reduce the weight, the honeycomb filler structure is optimized at the third stage by varying the angle of opening of the cell of irregular hexagonal shape and coefficient of its shape in each section of the structure. Implementation of the suggested approach in weight optimization of a real object’s structural parameters showed its efficiency, expressed in a significant reduction of the optimal structure’s weight compared to its initial variant.