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Preprocessor
Preprocessing data for Lagamine program.
This page contains a description of the data to be indicated in the *.lag file for the Prepro.
Title
| Format (9A8,I3) | |
|---|---|
| Title(9) | Title, in 72 characters |
| I99999 | Big mesh index: = 1 if NUMNP (total number of nodal points)>99999 = 0 else |
Control data of the program
The control data is defined in 4 lines (in exponent, column on which the variable must be fit in with).
| 1st line (14I5) or (2I5, I10, I5, I10, 10I5) if I99999=1 | |
|---|---|
| NTANA5 | Type of analysis (see here) |
| IANA10 | Type of problem: |
| =1 - Plane stress state ($EP\sigma$) | |
| =2 - Plane strain state ($EP\varepsilon$) | |
| =3 - Axisymmetric state ($axi$) | |
| =4 - 3D state ($3D$) | |
| =5 - Generalized plane state ($EPG$) | |
| NUMNP15 or 20 | Total number of nodal points |
| NELTP20 or 25 | Number of ELement Types used (or groups) |
| MELEM25 or 35 | Total number of elements (all types together) |
| NDISP30 or 40 | Number of degrees of freedom where non zero DISPlacements are imposed |
| NFOUN35 or 45 | Number of foundations |
| NSEGT40 or 50 | Total number of segments defining the NFOUN foundations |
| IPILO45 or 55 | Number of pilot nodes for the foundations |
| NLAW50 or 60 | Number of constitutive LAWs used |
| IRICE55 or 65 | Indicator for the bifurcation calculation (RICE's criterion) – No more used. |
| ICGEO60 or 70 | Indicator for geometrical distortions (%age of distorted elements) |
| IERRO65 or 75 | Indicator for a posteriori error calculations |
| ICRIT70 or 80 | = 0 nil |
| = 1 forging simulation, criteria calculation to detect the too-distorted elements and automatic remeshing if the number of distorted elements exceeds the maximum fixed in the execution data and existence of “EI” (M. Dyduch) | |
| = 2 simulation with shearing bands and automatic remeshing if the number of bifurcated elements exceeds the maximum fixed in the execution data | |
| = 5 simulation where the VILOTTE's criterion is used as indicator | |
| = 6 forging simulation, different from Dyduch | |
| = 7 proportional fatigue computation (see fatigue calculation in Hill_3D_KI law), you must generate the file 61 (.ntfdam) | |
NTFDAM file structure
→ for mono-block loading:
| 1st line (I5) | |
|---|---|
| NL | =1 (NL is the number of blocks) |
| 2nd line (I10, G7.5) | |
| ncycle | =0 |
| PERIODE | =input value |
→ for multi-block loading:
| 1st line (I5) | |
|---|---|
| NL | = number of blocks |
| 2nd line (I10, G7.5) - repeated NL times | |
| ncycle | input value |
| PERIODE | input value |
Remark on NTANA
In general, a node has 3 DOF displacements and 1 DOF temperature. In the case of 3D shell elements, it has 3 DOF displacements and 3 DOF rotations. The variable NTANA allows the program to decide which is the maximum number of nodal DOF potentially useful for a given type of analysis (dimension NDOFN, classed as NSPAC, space dimension). It also allows to define the active DOF (i.e. those which can produce an equation) and the passive ones (which do not produce equations).
| NTANA | (2 translations + water pressure + air pressure + temperature) |
| = 1 - Plane mechanical analysis NDOFN = NSPAC = 3 : X,Y,T (no equation for DOF 3) |
|
| = 2 - 3D mechanical analysis NDOFN = NSPAC = 4 : X, Y, Z, T (no equation for DOF 4) |
|
| = 3 - Plane thermal analysis NDOFN = NSPAC = 3 : X, Y, T (no equation for DOF 1 and 2) |
|
| = 4 - Plane thermomech. analysis NDOFN = NSPAC = 3 : X, Y, T |
|
| = 5 - 2D coupled mechanical water – thermal – air flow analysis NDOFN = NSPAC = 5 : X, Y, PW, Pa, T |
|
| = 6 - 3D thermal. analysis NDOFN = NSPAC = 4 : X,Y,Z,T |
|
| = 7 - Plane mechanical analysis with shells NDOFN = NSPAC = 3 (2 translations, 1 rotation) X,Y,ZZ |
|
| = 8 - 3D mechanical analysis with shells NDOFN = NSPAC = 6 : X, Y, Z, ψ1, ψ2, ψ3 (3 translations + 3 coordinates of rotation vector) |
|
| = 9 - 3D thermomechanical. analysis NDOFN = NSPAC = 4 : X, Y, Z, T |
|
| = 10 - Plane mechanical analysis, second gradient method (Ouafa ElHammoumi) NDOFN = NSPAC = 5 : X, Y, λ, $\frac{d\lambda}{dX}$,$\frac{d\lambda}{dY}$ |
|
| = 13 - 3D coupled mechanical water – thermal – air flow analysis NDOFN = NSPAC = 6 : X, Y, Z, PW, Pa, T |
|
| = 14 - Plane mechanical analysis, second gradient method (Grenoble) NDOFN = NSPAC = 6 : X, Y, V11, V12, V21, V22 (ou λ11, λ12, λ21, λ22 for central node) |
|
| = 15 - 2D coupled mechanical water – thermal – air flow – chemical analysis NDOFN = NSPAC = 6 : X, Y, PW, Pa, T, c |
|
| = 16 - Plane coupled mechanical water flow analysis, second gradient method (Grenoble) NDOFN = NSPAC = 7 : X, Y, PW, V11, V12, V21, V22 (ou λ11, λ12, λ21, λ22 for central node) |
|
| = 17 - Plane coupled mechanical water – thermal – air flow analysis, second gradient method (Grenoble) NDOFN = NSPAC = 9 : X, Y, PW, Pa, T, V11, V12, V21, V22 (ou λ11, λ12, λ21, λ22 for central node) |
|
| = 18 : 2D coupled mechanical water – thermal – air flow – chemical analysis NDOFN = NSPAC = 8 : X, Y, PW, Pa, T, c1, c2, c3 |
Remark on IANA=5 (genralizes plane state)
- The last node is a special one; it always has 3 DOF, $\alpha_0$, $\alpha_1$ et $\alpha_2$, such that the thickness (in z direction) of a slice of slid varies according to: $b = \alpha_0 + \alpha_1 X + \alpha_2 Y$
- To be consistent with these 3 DOF of the last node, it is necessary to specify NTANA such that there exists at least 3 active DOF per node but may perhaps fix the non-significant ones.
For example, for the mechanical generalized plane state, NTANA = 7, IANA = 5 and fix the 3rd DOF for all the nodes (except for the last one eventually). - Initial values of $\alpha_0$, $\alpha_1$ et $\alpha_2$ can be introduced: they are the “coordinates” of the last node.
2 remarkable particular cases are worth noting :- Plane strain state : $\alpha_0$ = 1, $\alpha_1$ = $\alpha_2$ = 0 (and $\alpha_i$ all fixed)
- Axisymmetric state : $\alpha_0$ = 0, $\alpha_1$ = 1, $\alpha_2$ = 0 (and $\alpha_i$ all fixed).
- The last node appears in all the elements; therefore, the bandwidth is maximum → use the skyline system solver.
prepro.1560330254.txt.gz · Last modified: 2020/08/25 15:36 (external edit)
