Modelling of the Contact Behaviour Between Fine Adhesive Particles with Viscous Damping
On the basis of reference particle systems the single contact of two smooth spherical particles is shown. The comprehensive force displacement models of elastic-plastic, adhesive and frictional contacts are discussed. Titania and micro glass particles are selected on basis of their different physical properties. Therefore the model “stiff particles with soft contacts” is used to quantify and compare the elastic-plastic and frictional contact properties. The varying adhesion forces between the particles directly depend on this “frozen” irreversible deformation. So the adhesion force depends on the previous normal force as a history parameter.
The contribution of the load-dependent adhesion force to the tangential force in an elastic-plastic frictional contact, the rolling resistance and the torsional moment is also shown. In addition, the role of the contact consolidation coefficient is discussed. For relatively slow (quasistatic) motion and flow rates v < 1 m/s, the velocity-dependent damping force is assumed to be negligible. For processes with higher velocities, this assumption is not valid. Thus, the velocity-dependent viscous damping model by Tsuji et al. (