Influence of 3D microstructure for improving the thermal performance of building façades

The thermal performance of a building is highly dependent on the heat transmission through the envelope. On the other hand, additive manufacturing has been increasingly used in several industrial applications due to its possibility to produce complex structures. However, most studies of the 3d printing process focused on mechanical performance. This study aims to evaluate how the internal 3D-printed microstructure affects thermal performance. Twelve infill patterns were analysed, including Gyroid, Grid, Hilbert curve, Line, Rectilinear, Stars Triangles, 3D Honeycomb, Honeycomb, Concentric, Cubic, and Octagram spiral. Using fused deposition modelling (FDM), the samples were printed with polyethene terephthalate-glycol (PET-G) thermoplastic filaments. Thermal tests were conducted using a calibrated hotbox, following the recommendations of ASTM C1363-11:2014. The results obtained show a variation of 70% by changing the internal microstructure using fix infill density of 25%. Concentric, Gyroid and Hilbert curve achieved the best thermal insulation properties.