Table of Contents
EHYPOFE2
Plane or axisymmetric state
Description
2D Multi-scale Coupled Analysis:
Water-Air-Pollutant.
Type: 284
The element is defined by 4 or 8 nodes indicated in NODES according to the order presented in the Figure. 4 integration points are used for the interpolation.
Remark: the convergence is better with 4 nodes than with 8 due to numerical oscillations.
The mechanical constitutive laws that can be used with this element are, for instance:
- ELA: Elastic constitutive law
Implemented by: A. Fanara based on the work of F. Bertrand, 2020
Files
Prepro: EHYPOFE2A.F
Lagamine: EHYPOFE2B.F
Input file
| Title (A5) | |
|---|---|
| TITLE | “EHYPO” |
| Control data (2I5) | |
|---|---|
| NELEM | Number of elements |
| INSIG | = 0 → No initial stress = 1 or 2 → Initial stresses |
| Initial stresses - Only if INSIG > 0 (4G10.0) | |
| If INSIG=1: $\sigma_y=\sigma_{y0}+yd\sigma_{y}$ If INSIG=2: $\sigma_y=min(\sigma_{y0}+yd\sigma_y,0)$ |
|
| SIGY0 | $\sigma_{y0}$ effective stress $\sigma_y$ at the axes origin |
| DSIGY | Effective stress gradient along Y axis |
| AK0X | $k_0$ ratio $\sigma_x/\sigma_y$ |
| AK0Z | $k_0$ ratio $\sigma_z/\sigma_y$ (if AK0Z=0, AK0Z=AK0X) |
| The computation of SIGY0 and DSIGY must take into account the apparent specific mass, defined as \[\rho_a'=[(1-n)\rho_s+nS_w\rho_w]-\rho_w\] where: $\rho_s$ is the solid specific mass - this represents the specific mass of a fictive sample where ther is no porosity, i.e. where the grains occupy the whole volume of the sample $\rho_w$ is the fluid specific mass $n$ is the porosity defined in the flow law related to the element $S_w$ fluid saturation, ∈ [0,1] |
|
| Definition of the elements (6I5/4 or 8I5) | |
|---|---|
| NNODM | Number of nodes for the mechanical description: 4 or 8 (preferred 4) |
| NINTM | Number of integration point for the mechanical description: 4 |
| LMATM | Mechanical law |
| NNODP | Number of nodes for the fluid description: 4 or 8 (preferred 4) |
| NINTP | Number of integration points for the flow description: 4 Must be equal to NINTM |
| LMATF | Flow law |
| NODES(NNODEM) | List of nodes |
| Definition of the elements in the microstructure | |
|---|---|
| Line 1 (1I5) | |
| NUMEL2 | Total number of micro-elements |
| Line 2→NUMEL2+1 (6I5) | |
| IELEM2 | Number of the micro-element |
| ILAW | Type of element: 1=bedding plane, 2=bundle of tubes, 3=bridging plane |
| NDUN | No. of the micro-node at corner 1 of the micro-element |
| NDDEUX | No. of the micro-node at corner 2 of the micro-element |
| NDTROIS | No. of the micro-node at corner 3 of the micro-element |
| NDQUTR | No. of the micro-node at corner 4 of the micro-element |
Results
- Stresses (in global axes)
- Mechanical stresses $\sigma_x$, $\sigma_y$, $\sigma_{xy}$, $\sigma_z$
- Flow of water $f_{wx}$, $f_{wy}$, $f_{we}$
- Flow of gas $f_{gx}$, $f_{gy}$, $f_{ge}$
- Advective and diffusive flow of pollutant $f_{px}$, $f_{py}$, $f_{pe}$
- Diffusion pollutant flux $f_{px,b},f_{py,b}$
- Internal variables:
- Internal variables of the mechanical law
- Internal variables of the flow law