The release of Rocky DEM 2022R1 has introduced a beta version of Smoothed particle hydrodynamics (SPH) that helps further the breadth of simulations made possible in Rocky DEM. SPH is a computational technique that uses a collection of discrete particles to simulate specific solid mechanics and fluid flows. A Lagrangian method originally developed for astrophysics simulations, SPH is a powerful tool in modelling fluid flows with high viscosity, high deformation and free surface flows. SPH is also a mesh-free method and thus the fluid flow does not need to be meshed into cells before a simulation.
The integrated Rocky SPH module shines in multiphase flows with a high solid density and free surface flows. The benefit of SPH simulations in Rocky DEM software is that it allows for particle - SPH interactions which is ideal for simulating slurry materials which can’t precisely be modelled purely as a fluid or with purely solid particles. Rocky allows the user to mix the required amount of solid and liquid particles to accurately simulate their interactions. It is also typically considered difficult to set inlet conditions in SPH, however this Rocky module seamlessly integrates with pre-existing Rocky volume fills and continuous inlets to simplify the process. While SPH simulations need to perform computations for a higher number of neighbouring particles, the calculations can be run on multi-GPU with minimal effort using Rocky's simulation execution target settings.
The properties and behaviour of the smoothed particles can be defined by density, size, viscosity and speed of sound in medium. A variety of boundary, turbulence, position correction and viscosity models allow for SPH to be used for simulations in a wide range of contexts. A large range of corrections, limits and factors allow the user to fine tune the particle's behaviour for a variety of use cases. A more in depth documentation about the SPH method and Rocky implementation can be found on the ROCKY customer portal.
“Weir Minerals is continuously pursuing accurate modelling of motion and breakage of ore particles within SAG mills. The new coupled DEM-SPH model available in Rocky DEM is a great step towards measuring the discharge of the mill by accurately modelling the breakage of coarse material and the transport of the finer material within the grinding and pulp chambers.”
Dr. Nirmal Weerasekara, Principal Engineer, Weir Minerals
For more information on the broader capabilities of Rocky DEM, please visit LEAP's Rocky DEM webpage here.