FINITE-ELEMENT ANALYSIS OF HYBRID GRID-STIFFENED HONEYCOMB CORE SANDWICH PLATES FOR STRUCTURAL PERFORMANCE ENHANCEMENT

Abstract

Use of honeycomb sandwich structures is increasing in many engineering applications in aircraft, automobile, and other industries, due to their high flexural strength-to-weight ratio. Naturally, the challenge on further increasing their strength-to-weight ratio is an active research objective in this area. Grid stiffeners are known for their high bending strength. Hence, to combine the advantages of both of the honeycomb core and grid stiffeners, this paper investigates the possibility of enhancing the structural performance of composite sandwich panels by using a hybrid-grid-stiffened honeycomb sandwich composite panel. Towards this, an ortho-grid structure is considered to be combined with the honeycomb core, to raise the overall stiffness. Response under static uniformly distributed transverse load is simulated using finite-element software ANSYS to compare the performance of sandwich structures of different types of core, namely, aluminum grid-stiffened core, aluminum honeycomb core, and an aluminum hybrid-ortho-grid-stiffened honeycomb core. Based on this FE analysis, the mechanical characteristics like bending stiffness, transverse displacement, and specific bending stiffness are evaluated for these three types of sandwiches, to compare their performance. Some further parametric studies are also carried out. The results from the present research indicate that the grid-stiffened-honeycomb core is a bit heavier than honeycomb core, but load-carrying capacity and more importantly the specific strength is considerably improved. This promises to improve the overall properties of sandwich structures.