  Introducing a reduced particle stiffness in discrete element method (DEM)
allows for bigger time steps and therefore fewer total iterations in a
simulation. Although this approach works well for dry non-adhesive particles,
it has been shown that for fine particles with adhesion, system behaviors are
drastically sensitive to the particle stiffness. Besides, a simple and
applicable principle to set the parameters in adhesive DEM is also lacking. To
solve these two problems, we first propose a fast DEM based on scaling laws to
reduce particle Young's modulus, surface energy and to modify rolling and
sliding resistances simultaneously in the framework of Johnson-Kendall-Roberts
(JKR)-based contact theory. A novel inversion method is then presented to help
users to quickly determine the damping coefficient, particle stiffness and
surface energy to reproduce a prescribed experimental result. After validating
this inversion method, we apply the fast adhesive DEM to packing problems of
microparticles. Measures of packing fraction, averaged coordination number and
distributions of local packing fraction and contact number of each particle are
in good agreement with results simulated using original value of particle
properties. The new method should be helpful to accelerate DEM simulations for
systems associated with aggregates or agglomerates.
