A numeric value of one of the implemented data types as given in MaterialPropertyLib::PropertyDataType.
The numerical value of one of the implemented data types, as given in MaterialPropertyLib::PropertyDataType.
Scalars, vectors (2 or 3 components), symmetric 3D tensors (6 components) and
full tensors (4 or 9 components) are supported. Based on the number of
components, OGS will deduce the type of the quantity (scalar/vector/tensor,
1D/2D/3D) automatically.
The elements of `<values>` are in row-major order. I.e., if you write the
following into your project file
```
<value>
1 2
3 4
</value>
```
OGS will read the proper 2x2 matrix.
For the order of symmetric tensor components please refer to [the user guide](https://www.opengeosys.org/docs/userguide/basics/conventions/#symmetric-tensors).
@@ -88,13 +88,17 @@ This order is used, e.g., to display the per component convergence of the non-li
*[TwoPhaseFlow with PP](https://doxygen.opengeosys.org/d0/d3f/namespaceProcessLib_1_1TwoPhaseFlowWithPP.html#processvariablestpfwpp)
*[TwoPhaseFlow with Prho](https://doxygen.opengeosys.org/d4/de4/namespaceProcessLib_1_1TwoPhaseFlowWithPrho.html#processvariablestpfwprho)
## Kelvin mapping
## <a name="symmetric-tensors"></a> Symmetric tensors and Kelvin mapping
To map the elasticity/stiffness tensor OpenGeoSys internally uses a Kelvin mapping with an adapted component ordering for computational reasons \[[1](https://arxiv.org/abs/1605.09606)\].
For 2D, the Kelvin-Vector of the stress tensor looks like $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sqrt{2}\sigma_{xy})$ whereas the 3D version reads as $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sqrt{2}\sigma_{xy}, \sqrt{2}\sigma_{yz},\sqrt{2}\sigma_{xz})$. The actual output consists of the full (symmetric) tensor elements (without the factor $\sqrt{2}$) retaining the same order.
For 2D, the Kelvin-Vector of the stress tensor looks like $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sqrt{2}\sigma_{xy})$ whereas the 3D version reads as $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sqrt{2}\sigma_{xy}, \sqrt{2}\sigma_{yz},\sqrt{2}\sigma_{xz})$.
For Kelvin mapping also see the [conversion function documentation](https://doxygen.opengeosys.org/d6/dce/namespacemathlib_1_1kelvinvector#ad78b122c10e91732e95181b6c9a92486).
The input and output of symmetric tensors consists of the full (symmetric) tensor elements (without the factor $\sqrt{2}$), retaining the same order.
I.e., Input and output components are be $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sigma_{xy})$
and $\sigma=(\sigma_{xx},\sigma_{yy},\sigma_{zz},\sigma_{xy},\sigma_{yz},\sigma_{xz})$, respectively.
## Staggered Scheme
A staggered scheme solves coupled problems by alternating on separate physical domains (e.g. thermal and mechanical) in contrast to monolithic schemes which solve all domains simultaneously (e.g. thermomechanical).
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@@ -138,4 +142,4 @@ For isotropic, linear elasticity we provide the interval [[2]](#2) and the recom
