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Smooth-Particle Phase Stability with density and density-gradient potentials

Wm G Hoover·Carol G Hoover
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Abstract

Stable fluid and solid particle phases are essential to the simulation of continuum fluids and solids using Smooth Particle Applied Mechanics. We show that density-dependent potentials, such as Phi=(1/2)Sum (rho-rho_0)^2, along with their corresponding constitutive relations, provide a simple means for characterizing fluids and that a special stabilization potential, Phi=(1/2)Sum (delrho)^2, not only stabilizes crystalline solid phases (or meshes) but also provides a surface tension which is missing in the usual density-dependent-potential approach. We illustrate these ideas for two-dimensional square, triangular, and hexagonal lattices.

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Wm G Hoover, Carol G Hoover. 2005-09-13. Smooth-Particle Phase Stability with density and density-gradient potentials. https://doi.org/10.1103/physreve.73.016702

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