Changelog/Release Notes#

On this page we provide a summary of the main API changes, new features and examples for each release of Ratel.

Current `main` branch#

Update strain energy function to the convex form for both Neo-Hookean and Mooney-Rivlin models.
Add mixed linear elasticity and Neo-Hookean hyperelastic models for incompressible materials.
Add linear plasticity with linear hardening model for small strains.
Add pressure boundary loading which is caused by liquids or gases on the surface of the solid structure.
Add flexible clamp, slip, traction, and platen boundary conditions with more complex time variance during a quasistatic or dynamic simulation.
Add robust surface force and surface centroid monitoring options.
Add command-line validation options for maximum displacement and per-face centroids and surface forces.
Add isochoric Ogden hyperelastic model in initial configuration.
Add mixed Ogden hyperelastic model in initial configuration.
Add isochoric Neo-Hookean model in initial configuration.
Add Mooney-Rivlin hyperelastic model in current configuration.
Add Coulomb friction capabilities to platen contact boundary conditions.
Add isochoric Mooney-Rivlin model in initial configuration.
Add CEED benchmark problems 1, 2, 3, and 4 for convergence testing and benchmarking.
Setup dynamic solver for mixed linear elastic and hyperelastic models.

Rename Ratel[TS,SNES,KSP]SetupPCMG to Ratel[TS,SNES,KSP]SetupPC for better accuracy.
Rename RatelSolverType, RatelMultigridType, and some function names for consistency.
Refactor p-multigrid support as registered PETSc PC; this change generated various API and command line option changes.
Rename material parameter contexts as follows:
- LinearElasticityParams
- NeoHookeanPhysics to NeoHookeanElasticityParams (alias of LinearElasticityParams)
- MooneyRivlinPhysics to MooneyRivlinElastictictyParams
Remove material-specific platen contexts
Rename cell-to-face surface force functions to be suffixed with CellToFace and -ts_monitor_surface_force to -ts_monitor_surface_force_cell_to_face to prevent accidental usage
Rename reaction force functions *ReactionForce* to *SurfaceForce* and -ts_monitor_reaction_force to-ts_monitor_surface_force
Deprecate -ts_monitor_reaction_force

See the Using Ratel section for the updated command line options.

Bugfix to make tet based tests optional in the test suite.

Expanded features and material models.

Add RatelComputeSurfaceForces for computing final forces on surfaces, identified by DMPlex face id number.
Add support for computing Jacobians from strain energy density functional from residual evaluation via Automatic Differentiation with Enzyme-AD. Neo-Hookean material models provided in current and initial configuration.
Add support for platen boundary condition based upon Nitsche’s method.
Add support for restart from saved binaries of state vectors.

Update names and command line arguments for material models for consistency.
Use PETSc option options_file over redundant yml option in tests and examples; removed options_yml argument from RatelInit.
Docker images built and tested as part of CI process for latest main.
Update Boolean arguments -view_diagnostic_quantities and -ts_monitor_diagnostic_quantities to use viewer type.
Remove command line option -output_dir; this functionality is provided with setting the output filepath for the viewer via -view_diagnostic_quantities and -ts_monitor_diagnostic_quantities.
Remove RatelVectorView in favor of base PETSc functionality.

Internal refactor around RatelMaterial, an object representing a region of the mesh given by a material model with consistent physical parameters. External behavior was not affected by this refactor.

Bugfix for install paths in makefile.

Bugfix for Mass QFunction source file relative path.

Initial Ratel API. The Ratel solid mechanics library is based upon libCEED and PETSc. libCEED v0.10.1 or later and PETSc v3.17 or later is required.