11. Modeling I

11.1. Characteristics of modeling

We use a AXIS model (quadratic elements).

The continuous contact formulation is used. This test case is used to validate the CONTACT_INIT = “INTERPENETRE” feature. Here we use the GLISSIERE function, which makes it possible to maintain contact throughout the extrusion, mathematically. The result is physically similar to modeling without a slide, since it is a frictionless extrusion.

11.2. Characteristics of the mesh

Number of knots: 1174

Number of meshes: 510 TRIA6 and 152 SEG3

Number of nodes in contact: 38

11.3. Tested sizes and results

The reference values are considered to be those of the C modeling.

The following displacement \(Y\) of the point \(K\) of the piece of paper with respect to the surface \(\mathrm{ABCDEFG}\) of the die is tested.

Identification	Reference type	Reference value	Tolerance
Point \(K\)/Point \(B\) - \(\mathrm{DY}\)	“ANALYTIQUE”	5.0000	0.1%
Point \(K\)/Point \(F\) - \(\mathrm{DY}\)	“NON_REGRESSION”	144.9480	0.1%

11.4. notes

The calculation is carried out by imposing a displacement on the back side of the block \(\text{(MN)}\). The displacement is imposed as follows:

from	\(\mathrm{0.mm}\) to	\(\mathrm{5.mm}\) in 5 steps
from	\(\mathrm{5.mm}\) to	\(\mathrm{20.mm}\) in 15 steps
from	\(\mathrm{20.mm}\) to	\(\mathrm{50.mm}\) in 10 steps
from	\(\mathrm{50.mm}\) to	\(\mathrm{70.mm}\) in 10 steps
from	\(\mathrm{70.mm}\) to	\(\mathrm{140.mm}\) in 35 steps
from	\(\mathrm{140.mm}\) to	\(\mathrm{155.mm}\) in 15 steps

The calculations do not converge with the default keywords used for convergence in STAT_NON_LINE, because the default value of RESI_GLOB_RELA = 1.E-6 is too restrictive (the forces to which the piece is subjected are initially relatively weak). To overcome this problem, use the keyword RESI_GLOB_MAXI = 1.E-6.