4. B modeling

We will start again with modeling A. The mesh is the same as that of modeling A but it has changed to quadratic.

4.1. TP implementation

4.1.1. Continuous formulation

Convert the mesh from modeling A to a quadratic mesh in the Mesh module (Menu Modification → Convert to/from quadratic)

In order to take full advantage of quadratic elements and to obtain a smooth pressure profile, it is important to place the middle nodes on the geometry during the conversion (check the «  Medium nodes on geometry «  box during the conversion) .

Change the contact method and use the wording “CONTINUE”. Observe the contact pressure obtained using the degree of liberty LAGS_Cdu field DEPL. Compare to the contact method by default. What are we seeing? Which of the methods provides the best approximation?

To obtain a correct pressure profile, use a diagram for integrating contact terms at Gauss points ( INTEGRATION =” GAUSS “in the DEFI_CONTACT/ZONE command).

In order to remove the alarm that appears with the default settings, it is necessary to impose REAC_ITER =1 under the keyword factor NEWTONde the command STAT_NON_LINE (in continuous formulation, the tangent matrix is necessarily rebuilt at each iteration) .

4.2. Tested sizes and results

Identification	Reference type	Reference value	Tolerance
\(\mathit{DEPL}\) \({\mathit{LAGS}}_{C}\) dot \(\mathit{C1}\)	“ANALYTIQUE”	\(\mathrm{-}\mathrm{2798,3}\mathit{Mpa}\)	3.0%