Automate the mesh-independence heuristic for problems without exact solutions (verify_mesh_independence)

README.md

@@ -186,6 +186,7 @@ FEniCSx     deal.II      4C   NGSolve   skfem   Kratos    DUNE    FEBio
 | `prepare_simulation` | Knowledge + real examples + template in one call — always the first step |
 | `run_simulation` | Execute Python-based solvers (FEniCSx, NGSolve, scikit-fem, DUNE-fem) |
 | `run_with_generator` | Generate input + run compiled solvers (4C, deal.II, Kratos) |
+| `verify_mesh_independence` | Heuristic mesh-refinement study for problems without an exact solution: re-runs at refined resolutions, compares global norms + probe values, converged/not-converged verdict |
 | `knowledge` | Physics knowledge, pitfalls, materials, coupling docs, cross-backend collation |
 | `examples` | Real test files from the solvers' own test suites |
 | `couple` | General partitioned coupling for any physics (contract + Aitken relaxation) |

src/backends/dune/backend.py

@@ -251,6 +251,19 @@ def supported_physics(self) -> list[PhysicsCapability]:
                 element_types=["Lagrange-P1", "Lagrange-P2"],
                 template_variants=["2d"],
             ),
+            PhysicsCapability(
+                name="poisson_mms",
+                description=(
+                    "3D variable-coefficient Poisson manufactured-solution "
+                    "(MMS) convergence family — -div(kappa grad u) = f on "
+                    "[0,L]^3, affine kappa, exact Dirichlet data, uniform "
+                    "refinement with per-level L2/H1 error lines; L2 order "
+                    "k+1 / H1 order k verified live"),
+                spatial_dims=[3],
+                element_types=["Lagrange-P1", "Lagrange-P2",
+                               "Lagrange-P3", "Lagrange-P4"],
+                template_variants=["3d_varcoeff"],
+            ),
             PhysicsCapability(
                 name="heat",
                 description="Steady heat conduction (UFL)",

src/backends/dune/generators/__init__.py

@@ -1,6 +1,7 @@
 """DUNE-fem generator registry — maps physics_variant -> generator function."""
 
 from .poisson import GENERATORS as _poisson_gen, KNOWLEDGE as _poisson_kn
+from .poisson_mms3d import GENERATORS as _poisson3d_gen, KNOWLEDGE as _poisson3d_kn
 from .heat import GENERATORS as _heat_gen, KNOWLEDGE as _heat_kn
 from .linear_elasticity import GENERATORS as _elast_gen, KNOWLEDGE as _elast_kn
 from .stokes import GENERATORS as _stokes_gen, KNOWLEDGE as _stokes_kn
@@ -13,7 +14,7 @@
 # Merged generator registry: physics_variant -> callable(params) -> str
 GENERATORS: dict[str, callable] = {}
 for _g in [
-    _poisson_gen, _heat_gen, _elast_gen, _stokes_gen,
+    _poisson_gen, _poisson3d_gen, _heat_gen, _elast_gen, _stokes_gen,
     _rxn_gen, _nonlinear_gen, _dg_gen, _adaptive_gen,
     _advanced_gen,
 ]:
@@ -22,7 +23,7 @@
 # Merged knowledge registry: physics_name -> dict
 KNOWLEDGE: dict[str, dict] = {}
 for _k in [
-    _poisson_kn, _heat_kn, _elast_kn, _stokes_kn,
+    _poisson_kn, _poisson3d_kn, _heat_kn, _elast_kn, _stokes_kn,
     _rxn_kn, _nonlinear_kn, _dg_kn, _adaptive_kn,
     _advanced_kn,
 ]: