Limitations about phasefieldX

[AqeelNawaz1623]

Hi. i want to know the limitations of phasefieldx. Does it have capabilities like Multi material handling , Interface modelling,
Viscoelastic Material Model (Prony series etc), Thermal coupling , Finite strain, adaptive time-stepping, mesh adaptivity, rate-dependent fracture etc. Or we have to code these separately. also from where i can get the List of degradation functions or
List of solvers phasefieldx has builtin.
thanks.

[CastillonMiguel]

Hi,

Below is a summary of the current capabilities and limitations of PhaseFieldX:

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Multi-material handling

Yes, multi-material problems can be handled.

Since PhaseFieldX is built on top of FEniCSx, you can define different material properties using subdomains. The simplest approach is to define material parameters over marked subdomains without modifying the internal PhaseFieldX code.

You can follow this FEniCSx tutorial as reference:
https://jsdokken.com/dolfinx-tutorial/chapter3/subdomains.html

With this approach, multi-material simulations can be performed directly.

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Interface modelling

The models implemented in PhaseFieldX are based on the general phase-field fracture framework (diffuse crack approach), as described in the documentation.

Classical cohesive interface models (sharp interface CZM-type formulations) are not implemented. The current approach assumes a bulk phase-field description of fracture.

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Viscoelastic material models (Prony series, etc.)

Not implemented at the moment.

There is an open issue discussing possible future implementation of viscoelastic models:
#29

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Thermal coupling

Thermo-mechanical coupling is not currently implemented.

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Finite strain

Currently, the implemented models assume small strain kinematics.

Finite strain formulations are not available in the current version.

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Adaptive time-stepping

Adaptive time-stepping is implemented for the energy-controlled solver.

See for example:
https://github.com/CastillonMiguel/phasefieldx/blob/main/src/phasefieldx/Element/Phase_Field_Fracture/solver/solver_ener_non_variational.py

The theoretical background of this strategy is described in:
https://www.sciencedirect.com/science/article/pii/S0142112325005948

The same scheme can be adapted to other solvers if required.

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Mesh adaptivity

Mesh adaptivity is not implemented.

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Rate-dependent fracture

Not implemented explicitly. The current framework focuses on standard rate-independent phase-field fracture models.

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Degradation functions

The degradation functions are defined in:

https://github.com/CastillonMiguel/phasefieldx/blob/main/src/phasefieldx/Element/Phase_Field_Fracture/g_degradation_functions.py

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Built-in solvers

The available solvers are located here:

https://github.com/CastillonMiguel/phasefieldx/tree/main/src/phasefieldx/Element/Phase_Field_Fracture/solver

These include:

• Staggered schemes
• Energy-controlled solvers
• Non-variational solver variants

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If you need features such as viscoelasticity, thermal coupling, finite strain, or mesh adaptivity, these would require extending the current framework.

Best regards.

[AqeelNawaz1623]

Thank you for clarification. Regards