Optimization Design And Mechanical Analysis Of Textile-reinforced Composite Folded Cores

Aircraft designers are always aiming at the decreasing of the weight in the aircraft. The weight ofthe aircraft depends on the reasonable structural design concepts, the advanced structural materialsand the efficient structural pattern. As a result, we must focus on these aspects if we want to save theweight of the aircraft as much as possible. However, the structural design concepts are limited to thedevelopment of the mechanical theory, and the structural materials are limited by the development ofthe material science. Therefore, if we want to reduce the weight of the aircraft in a short timeefficiently, we must try to explore new structural patterns. Because of its special configuration,sandwich structures with folded core are more designable in comparison to other structures such asstiffened panel, honeycomb sandwich panel.In this paper, the equivalent mechanical property and the parametric optimization of the V typefolded core made of composite laminate have been studied in this paper. Firstly, based on the classicallaminate theory and the mechanical analysis of the folded core cell, the equivalent theoretical elasticmodule Ezand equivalent theoretical shear module Gxzof the V type composite folded core was gotby analyzing the mechanical property of the folded core cell. The equivalent modules of the foldedcores were compared with the one of the honeycomb cores then. Secondly, the finite element model ofthe cell was established by the FEM software Patran/Nastran, and mechanical property of the V typecomposite folded core was analyzed numerically. Finally, aiming at maximizing the equivalentmodules, the structural parameters of the folded cores made of composite laminate were optimizedunder the constraint of certain areal density by the multidisciplinary optimization software iSIGHT.The optimal solution was obtained by optimizing the surrogate model set up by the analysis results ofthe selected62kinds of different folded cores. In a conclusion, the consequences given in this paperprovided a simple and reliable approach to researching the equivalent mechanical property of the Vtype composite folded core structure at the initial stage of design.