On a simple, stable and efficient bond model for inter-particle adhesion

Abstract

In this work, we explore the underlying structure of most common bond models used in particle dynamics and discrete element methods, to derive simple equilibrium conditions and stability requirements that must be fulfilled for a model to stand effective and reliable. We then propose a simple model taking into account such considerations, with which we are able to capture inter-particle bonding very straightforwardly once a given bonding criterion is met. The model can be particularized to work with different contact models, such as Hertzian contact, as well as with different adhesion models, such as the classical Johnson, Kendal and Roberts (JKR) model. The derived requirements yield guidelines that may help the selection of proper parameter values (such as, but not only, the stiffness of the bond) for most common bond models, thereby guiding (or even avoiding) burdensome problem-dependent calibration. Numerical examples are provided for illustration.