Modelling the anisotropic thermal conductivity of 3D logpile structures

Assessing and predicting the thermal conductivity (kappa) of macroporous materials is particularly important for additive manufactured 3D structures, as they offer considerable potential for tuning architectures and properties. In this work, finite element methods (FEM) are used to simulate the transient plane source test in 3D logpile lattices, approaching the effect of interfacial thermal contact resistances on kappa measurement. Besides, the influ-ence of different geometrical parameters (rod diameter, macropore size and overlapping between rods in consecutive layers) and the kappa of the strut material on the anisotropic thermal conductivity of 3D lattices are investigated. The models are validated using experimental data for 3D composite structures of gamma-Al2O3 with graphene nanoplatelet contents up to 18 vol%, as well as with reported data for alike scaffolds, all printed by robocasting. Results have strong impact for the application of novel 3D structures in energy production and storage, catalysis and heat transfer-related fields.