Rotating drum with conductive heat transfer (DEM)

This tutorial uses the discrete element method to simulate a rotating drum.  The drum is held at a fixed hot temperature of 600K and particles are initially placed in the drum with a temperature of 300K.  As the drum rotates, the particles slide along the surface of the wall and are warmed by conduction.  Radiative heat transfer is neglected, and heat is conducted through the particle-wall contact area as well as through the thin layer of interstitial gas between the wall and adjacent particles.