Heat Transfer Rates in Wall Bounded Shear Flows near the Jamming Point accompanied by Fluid-Particle Heat Exchange

We investigate the heat transfer rates through a contact network of a sheared granular
material using the Discrete Element Method (DEM). The tool ParScale enables us to study intra-
particle transport processes, and the DEM solver LIGGGHTS is used to carry out the simulations.
Our setup enables us to investigate a plethora of dimensionless parameters in order to picture
different phenomena occurring near the jamming point (e.g., solidification) of a sheared granular
material. Thereby, our main outcome is the quantification of thermal fluxes which occur due to (i)
conduction in case of particle-particle collisions, as well as (ii) convection due to random particle
motion. Also, the transferred heat between the particles and the ambient fluid is analyzed. In
addition, we analyse the phenomena of crystallisation, and its effect on the thermal transport
rate in the granular material. Again we exploit the measured thermal fluxes to decide whether a
system is crystallized or not. Furthermore, we demonstrate that the ordering process, and hence
the heat transport rate, can be affected by adjusting the coefficient of friction of the granular
material.