FEA Integration

This section explains how to use simcoon’s built-in constitutive models within commercial Finite Element Analysis (FEA) software on Linux systems.

Note

This is the opposite of the external plugin system documented in External. Here, simcoon models run inside commercial FEA software. In the external plugin system, external UMATs run inside simcoon’s solver.

Overview

Simcoon provides ready-to-use bridge files in the software/ directory that allow you to use all simcoon constitutive models directly in commercial FEA software:

For Abaqus:

• software/umat_singleM.cpp - Single mechanical model (selected by material name)

• software/umat_singleT.cpp - Single thermo-mechanical model

• software/umat_singleM_multi.cpp - Multiscale mechanical model

• software/umat_externalM.cpp - Template for custom external UMAT

For Ansys:

• software/usermat_singleM.cpp - Single mechanical model (selected by model code)

The bridge files:

1. Export an extern "C" function (umat_() or usermat_()) that the FEA software calls

2. Convert FEA arrays ↔ simcoon Armadillo format

3. Call simcoon’s select_umat_M() to run the appropriate constitutive model

4. Convert results back to FEA format

Supported FEA Software

• Abaqus Integration
  • Overview
  • Prerequisites
  • Using umat_singleM (Recommended)
  • Using umat_singleT (Thermo-mechanical)
  • Using umat_singleM_multi (Multiscale)
  • Using umat_externalM (Custom Model)
  • How It Works
  • Available Models
  • Troubleshooting
  • Complete Example
• Ansys Integration
  • Overview
  • Prerequisites
  • Using usermat_singleM.cpp
  • Model Codes
  • How It Works
  • Limitations and Workarounds
  • Troubleshooting
  • References

Key Differences

Comparison of FEA Interfaces

Feature	Abaqus	Ansys
Bridge file	umat_singleM.cpp	usermat_singleM.cpp
Entry point	umat_()	usermat_()
Model selection	Material name (first 5 chars)	Model code in props[0]
Voigt notation	(11,22,33,12,13,23)	(11,22,33,12,23,13)
Time step control	Yes (pnewdt)	No
Thermo-mechanical	umat_singleT.cpp	Not yet implemented

Available Models

All simcoon constitutive models are available through the FEA bridges:

Elasticity: ELISO (isotropic), ELIST (transversely isotropic), ELORT (orthotropic)

Plasticity: EPICP (isotropic hardening), EPKCP (kinematic), EPCHA (Chaboche), EPHIL (Hill), EPHAC (Hill-Chaboche)

Viscoelasticity: ZENER (single branch), ZENNK (N branches), PRONK (Prony series)

Shape Memory Alloys: SMAUT (unified), SMANI (anisotropic)

Damage: LLDM0 (Lemaitre-Chaboche)

Micromechanics: MIHEN (Mori-Tanaka), MIMTN (multi-phase), MISCN (self-consistent), MIPLN (layered)

See the individual Abaqus and Ansys pages for complete property and state variable specifications.