Usage notes#
Definitions and precautions for use#
A concept produced by MODI_REPERE should no longer be used afterwards to make calculations, Code_Aster does not remember the coordinate system in which the fields appear. Only prints or traces are legal.
Notes:
When a \(N\) node of the mesh is located on the \(\mathrm{Oz}\) axis (of the cylindrical coordinate system), we look for the average node of the geometric centers of the cells containing the node \(N\) for the calculation of the transition matrix in cylindrical coordinate system. If this mean node is also on the \(\mathit{Oz}\) axis, the calculation stops in fatal error.
When all the components of a node are not present in the field to be processed, nothing is written in the transformed field for this node. This is encountered for example with the elements of modeling COQUE_3D for which the nodes located in the middle of the faces do not have a translational degree of freedom. The displacement field from MODI_REPERE is therefore not calculated for these middle nodes of faces.
For cases TENS_2D, authorized fields are only those that have the \(\mathit{SIXX},\mathit{SIYY},\mathit{SIZZ},\mathit{SIXY}\) or \(\mathit{EPXX},\mathit{EPYY},\mathit{EPZZ},\mathit{EPXY}\) components.
For cases TENS_3D, authorized fields are only those that have the \(\mathit{SIXX},\mathit{SIYY},\mathit{SIZZ},\mathit{SIXY},\mathit{SIXZ},\mathit{SIYZ}\) or \(\mathit{EPXX},\mathit{EPYY},\mathit{EPZZ},\mathit{EPXY},\mathit{EPXZ},\mathit{EPYZ}\) components.
In the case of 1D_ GENE, only fields EFGE_ELNO, SIEF_ELNO, EFGE_ELGA, and SIEF_ELGA are allowed.
In the case of VECT_2D and VECT_3D only the fields DEPL, VITE,, ACCE, FORC_NODA, REAC_NODA and FLUX_NOEU. For 6-component nodes, the coordinate system is changed on the 3 degrees of freedom of translation and then on the 3 degrees of freedom of rotation.
Cylindrical matches#
For the expression of the constraints in a cylindrical coordinate system, the following matches are made (for simplification we note \(T=\theta\)):
Constraints in a Cartesian coordinate system |
Constraints in cylindrical coordinate system |
|
vector |
\(X\) |
\(R\) |
\(Y\) |
\(Z\) |
|
\(Z\) |
\(T\) |
|
tensor |
\(\mathrm{XX}\) |
\(\mathrm{RR}\) |
\(\mathrm{YY}\) |
\(\mathrm{ZZ}\) |
|
\(\mathrm{ZZ}\) |
\(\mathrm{TT}\) |
|
\(\mathrm{XY}\) |
\(\mathrm{RZ}\) |
|
\(\mathrm{XZ}\) |
\(\mathrm{RT}\) |
|
\(\mathrm{YZ}\) |
\(\mathrm{ZT}\) |
|