| name | elmer-sim |
| description | Use when driving Elmer FEM (open-source multi-physics finite-element suite from CSC-IT) via `.sif` solver-input files — heat/elasticity/electromagnetics/fluid multiphysics, through sim runtime one-shot execution on Linux. |
elmer-sim
You are connected to Elmer FEM via sim-cli.
Elmer is an open-source multi-physics FEM code from CSC (Finland). A
case is defined by:
.sif — Solver Input File (block-structured text)- mesh directory — referenced via
Mesh DB "." "meshname" in
Header block; contains mesh.header, mesh.nodes, mesh.elements,
mesh.boundary
Execution: ElmerSolver case.sif. Output: case.vtu (ParaView, name
set by Post File in Simulation block).
base/ — always relevant
| Path | What's there |
|---|
base/reference/sif_blocks.md | .sif block structure (Header, Simulation, Body, Material, Solver, BC). |
base/reference/mesh_workflow.md | ElmerGrid usage; native mesh format; Gmsh → Elmer conversion. |
base/reference/solver_catalog.md | Built-in solvers: HeatSolve, StressSolver, MagnetoDynamics, etc. |
base/snippets/01_heat_square.sif | Verified heat-equation E2E snippet. |
base/known_issues.md | Build flags, mesh conversion quirks. |
solver/26.1/ — Elmer FEM 26.1 specifics
solver/26.1/notes.md — source build info, dependencies.
Hard constraints
- Mesh directory must exist before solving. Reference via
Mesh DB "dir" "meshname" means files live in <dir>/<meshname>/.
- Block ordering matters: Header → Simulation → Constants → Body →
Material → Body Force → Initial → Equation → Solver → BC.
- Active Solvers list in an Equation block ties solvers to bodies.
Bodies without an Equation reference are passive.
- Acceptance != exit code. Check the
.vtu output or stdout
residual history for physical validity.
End closes every block — missing End causes cryptic parse
errors far from the mistake.
Required protocol
After sim check elmer: gather Category A inputs (physics, geometry
source for mesh, BCs, material properties, acceptance criteria).
Generate mesh (ElmerGrid from .grd, or Gmsh→Elmer). Write .sif.
Lint with sim lint. Run with sim run --solver elmer. Parse .vtu
or stdout for validation.
