Quantifying the Heterogeneous Anisotropic Thermal Performance of Extrusion-Based 3D Printed Structures (2025-09)¶

Extrusion-based 3D printed structures exhibit inherent anisotropy and heterogeneity, resulting in regional variations and directional dependencies in their heat transfer behaviour. The current research lacks systematic investigations quantifying how these structural characteristics affect thermal properties. This study presents a multiscale computational framework that combines experimental characterisation with numerical simulations to evaluate the thermal behaviour of extrusion-based 3D printed structures with heterogeneous anisotropic features. The research results demonstrate that spatial variations in porosity and material continuity constitute the primary factors governing thermal conductivity distributions. The combined influence of heterogeneous and anisotropic heat transfer mechanisms results in macroscopic anisotropic thermal conductivity of 3D printed structures. Quantitative validation demonstrates a 2.94 % relative deviation between simulated and experimental thermal conductivity values. The heat transfer simulations further reveal localised temperature variations surpassing 0.5°C, underscoring the critical role of surface topography in influencing thermal transport phenomena. The proposed methodology establishes a fundamental connection between multiscale structural characteristics and thermal performance in 3D printed components, with efficacy in evaluating complex heat transfer processes. The study will provide valuable guidance for the thermal performance optimisation and functional design of 3D printed building walls.