FESA is a C++17 finite element structural analysis solver project. The first milestone is a reference-verified linear static MITC4 shell solver with an Abaqus-compatible input subset, HDF5-oriented results, and explicit numerical conventions.

Current Phase 1 Direction

MITC4 shell element baseline formulation.
Linear elastic material.
Nodal loads and fixed boundary conditions.
Abaqus input subset with S4 mapped to FESA MITC4.
S4R deferred.
6 shell DOFs per node: UX, UY, UZ, RX, RY, RZ.
Small artificial drilling stiffness.
Constrained DOF elimination.
Full-vector reaction recovery.
double precision and int64 ids/indices/equation numbering.
Stored-reference comparison from references/*.inp and references/*_displacements.csv without requiring local Abaqus execution.

Reference Artifacts

Stored Abaqus examples live under references.

The initial accepted artifact pair is:

Reference CSV displacement columns use Abaqus labels Node Label, U-U1, U-U2, U-U3, UR-UR1, UR-UR2, UR-UR3, mapped to FESA UX, UY, UZ, RX, RY, RZ.

Documentation Entry Point

Start with docs/README.md.

The core project documents are:

Validation

The default repository validation command is:

python scripts/validate_workspace.py

With the Phase 1 CMake harness in place, this command configures CMake, builds the C++ tests, and runs CTest.