Abaqus hydrodynamic equation of state materials define pressure as a function of density and internal energy for high-pressure, shock, explosive, gas, and fluid-like Abaqus/Explicit analyses.
How It Works
The guide defines an equation of state as a volumetric constitutive relation where pressure is positive in compression and depends on density and specific internal energy. Abaqus/Explicit supports Mie-Gruneisen equations of state with a linear shock-velocity/particle-velocity Hugoniot form, tabulated equations of state linear in energy, P-alpha compaction for ductile porous materials, JWL high explosive equations of state, ignition-and-growth forms, ideal gas behavior, and user-defined EOS behavior through VUEOS.
EOS materials may have no shear strength or may be combined with isotropic elastic or viscous deviatoric behavior. They can also be combined with selected plasticity models and tensile failure for dynamic spall or pressure cutoff behavior. Unless a fully coupled temperature-displacement dynamic analysis is used, the EOS response assumes adiabatic conditions.
Why It Matters
EOS models shift material modeling from stress-strain elasticity to pressure-density-energy response. They are essential for impact, shock, explosion, compaction, and fluid-like explicit simulations where volumetric response controls wave speed, pressure, and stable time increment.