- The physics interface for Heat Transfer in Porous Media now accounts for multiple immobile solids. There are two choices for averaging the thermal conductivity: volume average and a power law formulation.
- The previous three separate formulations of Darcy’s law (pressure, pressure head, and hydraulic head) are available in one framework in version 4.0. This makes it possible to mix boundary and initial conditions using any of these formulations. The Porous Media and Subsurface Flow physics interfaces in version 4.0 are also able to use specifications of permeability or hydraulic conductivity as scalars or as a full tensor formulations.
- The physics interface for Poroelasticity includes a poroelastic material model for definition of isotropic, anisotropic, or orthotropic poroelastic materials. The material properties can be written in terms of bulk and shear modulus, Young’s modulus and Poisson ratio, Lamé constants, or pressure and shear velocities.
- A new physics interface for Solute Transport incorporates the old application modes for solute transport in saturated porous media and variable saturated porous media in one physics interface.
- A new physics interface for Fracture Flow enables the solution of Darcy’s Law in thin shells and fractures, without having to mesh along the thickness of a thin layer. This substantially improves performance for a given accuracy compared to previous versions.
- You can specify the unit of time in days and years in the time-dependent solver. This improves the usability for geotechnical processes compared to the use of seconds.
- Darcy’s Law can now handle variable densities.
All backward compatibility issues are planned to be solved for version 4.0a unless explicitly stated.
Special Basis Functions or Elements
None of the special basis functions or elements for the finite element formulation of flow problems featured in version 3.5a are available in version 4.0. However, the new stabilization functionality in version 4.0 for fluid flow is identical to using the bubble elements in 3.5a.
Other special elements that were available in 3.5a will not be re-implemented in version 4. The reason for this is that the stabilized formulation in version 4.0 gives high accuracy to a relatively small computational cost compared to the special elements.