v2606: New and improved numerics
TOP
The inverse-distance weighted cell-cell stencil for overset meshes has been made more robust in two key areas.
Fringe-to-fringe cascade prevention: OVERSET fringe cells are now pre-promoted to INTERPOLATED before the donor-search phase. This prevents fringe cells from being selected as donors for other OVERSET acceptors, which previously could create unsafe donor chains and crash the interpolation. Even when allowInterpolatedDonors is set to true, this guard takes precedence, as fringe-to-fringe donation is always unsafe.
Empty-stencil protection: When a donor cell becomes a HOLE after the donor-marking phase, e.g. via markPatchesAsHoles, the acceptor cell was previously left as INTERPOLATED with an empty stencil, causing the interpolation to crash. Multiple defensive checks have been added to detect and demote such cells to HOLE, ensuring the stencil remains consistent. Rare edge cases where the stencil is lost during compaction or map redistribution are also handled.
The result is a more robust overset interpolation that handles complex topological transitions without crashing, particularly in cases with overlapping regions where hole-cutting and donor search interact closely.
Source code
TOP
This release completes the extension of finite-area support to handle multiple areas, building on work that was started as part of the OpenFOAM-v2512 release.
Multiple area support allows different finite-area physics to be defined for different parts of the volume. For example, different two-dimensional thermal shells can be applied to some boundary areas while a film shell is applied to another boundary of the same volume. This is especially useful because it allows finite-area physics solvers to be embedded directly as part of the volume boundary conditions, e.g. thermal shells.
The changes to the setup have been made to be backwards compatible. If there is only a single (default) region, the setup is as before. When multiple area regions are involved, the setup is analogous to multi-region cases, except that each volume region can now have multiple finite-area definitions. The tutorial hotRoomWithThermalShell.multi-area provides a straightforward introduction to this setup.
In this release, the edge field handling has been updated to properly preserve the flux orientation and edge flipping in parallel. This is now applied consistently through the various decomposition, reconstruction, and redistribution tools. Existing parallel cases should continue to run, as the tooling automatically detects any existing or missing edge flipping addressing. However, newly created edgeProcAddressing will not generally be usable with older versions of OpenFOAM.
The previous release already added multi-area support for decomposition and reconstruction as well as a number of post-processing tools. This release extends that support to parallel redistribution as well.
For diagnostics, the foamToVTK utility now also supports edge field output, and the VTK diagnostics output has been extended for both checkFaMesh and makeFaMesh.
TOP
AMI caching was introduced in version v2512, providing a potential performance boost for rotating mesh cases. It works by caching the interpolation weights and addressing for re-use across multiple rotations, saving the assembly cost that would otherwise include multiple parallel reductions and limit scaling performance.
In some workflows it is desirable to clear the cache, e.g. when adopting different time-step strategies.
This is now available as a single-shot control when specifying AMI patches:
AMI1
{
cacheSize <size>;
cacheRestartTime <time>;
}When time >= cacheRestartTime, the cache is cleared and subsequently rebuilt on further evaluations.
Future releases may include multiple restart options depending on requirements.
Source code