Volume 1 - Issue 3, September - October 2025

Honeycomb sandwich structures have emerged as one of the most efficient lightweight materials in modern engineering due to their exceptional stiffness-to-weight ratio and tunable thermal properties. The thermal behavior of such structures is primarily governed by the geometry of the core cells, which dictate the heat flow paths between the top and bottom face sheets. Understanding this geometry-dependent heat transfer is crucial for aerospace, automotive, and thermal protection system applications where both structural integrity and heat dissipation are equally critical.
This study presents a comprehensive Finite Element Method (FEM) based steady-state and transient thermal analysis of honeycomb sandwich panels with three distinct core geometries—hexagonal, square, and triangular—modeled under identical material and boundary conditions. Aluminum alloy (AA 5052) was employed for the honeycomb core, while carbon fiber reinforced polymer (CFRP) face sheets provided lightweight structural support. The numerical simulations were conducted using ANSYS Workbench 2024R1, incorporating realistic heat flux loading (10,000 W/m²), convective cooling (h = 25 W/m²•K), and thermophysical material properties. Mesh convergence and thermal contact resistance between face sheets and the core were carefully modeled to ensure high numerical accuracy.
The results reveal a strong dependence of thermal performance on core geometry. The hexagonal honeycomb exhibited the highest effective thermal conductivity (18.7 W/m•K), followed by the square (16.4 W/m•K) and triangular (14.2 W/m•K) geometries. Temperature contour plots indicated more uniform heat distribution and minimal hotspots for the hexagonal core, while the triangular configuration showed localized thermal gradients due to limited conductive pathways. Transient thermal response analysis demonstrated that the hexagonal geometry stabilized fastest (42 s), reflecting its superior heat spreading capability. Model validation against analytical predictions of cellular solids showed an average deviation of less than 7%, confirming the credibility of the FEM approach.
Overall, the study establishes that core geometry optimization plays a pivotal role in enhancing the thermal performance of sandwich structures. The findings underscore the suitability of hexagonal configurations for high thermal flux applications, where rapid and uniform heat dissipation is required. These insights provide valuable design guidelines for aerospace panels, electric vehicle enclosures, and advanced composite systems, paving the way for future hybrid-material optimization and experimental validation.