Sub-pore scale analysis of particle-fluid heat conduction in granular materials

Abstract Investigating heat transfer in granular materials is of great importance to a variety of engineering fields. A set of fully-resolved CFD (Computational Fluid Dynamics) simulations of fluid flow through a face centred cubic packing were conducted to improve understanding of heat transfer phenomenon in granular materials with pore fluid flow. A subset of the domain comprising two pores and their connecting throat was isolated for detailed sub pore scale analysis. This subdomain (pore throat) was idealized as a fluid-filled pipe. The variation in the Nusselt number (a non-dimensional number characterising particle-fluid heat conduction) in the direction of flow in the pore throat was compared with conditions in a pipe with a constant cross-section. The analysis indicates that the non-constant cross-section of void-throat configurations in granular packings may contribute to efficient heat transfer in the granular packings.