Hydrodynamics with elastic objects

This is work by Joel Clemmer (Sandia) and Thomas O’Connor (CMU) using the new RHEO package they developed for LAMMPS. The videos are scaled up adaptations of example input scripts included in the LAMMPS distro and are further described in the papers cited below.

In the first video, a water balloon consisting of an elastic BPM (bonded particle model) membrane encasing an SPH fluid collides with a floor and rebounds. The color of fluid particles qualitatively indicates their vertical velocity.

In the second video, the water balloon is replaced by a brittle ovoidal object with a BPM shell that fractures on impact releasing the fluid.

The third video is of a solid column that is directionally heated on one side. As the solid melts, elastic bonds are deleted and fluid particles begin to flow downward. Surface fluid particles form a thin shell akin to oxidation that redirects flow. Particle temperature and oxidation status are indicated by color.

All visualizations were performed with OVITO.