A refined finite element analysis on the thermal conductivity of perforated hollow sphere structures

This work addresses the thermal properties of perforated hollow sphere structures. Hollow sphere structures are a new material with significant areas of application in thermal insulation, structural and acoustic damping and controlled deformation at low stress levels. The structures are assembled by single hollow spheres and can be joined for example by sintering. Finite element analysis is performed in order to determine the effective thermal conductivity. Special focus is given to the influence of the sintered contact area and the relative density on the thermal properties. In addition, different contact topologies are accounted for. The maximum observed thermal conductivity is only 1.82% of the base material conductivity λb which confirms the usability of the material for the purpose of thermal insulation.