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

Abstract

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.

Monolithic AM façade: multi-objective parametric design optimization of additively manufactured insulating wall elements

“…Three promising hypotheses for increasing the thermal insulation of AM elements emerge from their comprehensive study: filling voids with insulation material, the simultaneous extrusion of insulating matter, and changing the material composition. While some studies (Lopes et al, 2023;Piccioni et al, 2023) have delved into evaluating infill patterns for Fused Deposition Modeling (FDM) with plastic feed material, also targeting façade elements, this research focuses predominantly on AM concrete elements. This emphasis stems from their applicability for load-bearing building elements.…”

“…• Biomimetic design with cellular or lattice structures • Reducing the thermal conductivity of the AM material composition • Adding insulation material into voids or in between AM elements Lopes et al (2023) and Piccioni et al (2023) have evaluated in their studies infill patterns for Fused Deposition Modeling (FDM) with plastic feed material, targeting façade elements. Furthermore, research has explored various internal patterns focusing on E3DCP (Dielemans et al, 2021;Marais et al, 2021;Suntharalingam et al, 2021;Briels et al, 2022;Cuevas et al, 2023) but also considered different infills, ranging from stationary air and foam concrete to additionally inserted insulating materials.…”