Standard Rolling Friction

Rolling friction is accounted for by applying a torque to the contacting surfaces in simulations where rolling friction is important.

with μ_r the coefficient of rolling friction, R_i the distance of the contact point from the center of mass and ω_i, the unit angular velocity vector of the object at the contact point.

EDEM provides the option to include a component of torque arising from rolling friction in geometry torque and power calculations. This component of torque is neglected (Off) by default.

You can select to include or neglect this component of torque by clicking the icon on the selected Particle to Geometry contact model.  The checkbox is unchecked by default, and selecting the Apply the torque resulting from the rolling friction model to the geometry elements includes the torque which is the same as EDEM v2017 and earlier.

In EDEM v2018 and earlier, this component of torque was included (On) by default. Including this component means geometry torque and power calculations are mesh size sensitive. Particle behavior is not influenced by including or neglecting this component of torque.