Contact Analysis (Part 1)

This analysis uses the data of tutorial/09_contact_hertz.

Analysis target

The analysis is a Hertz contact problem and the geometry to be analyzed is shown in Figure 4.9.1 and the mesh data is shown in Figure 4.9.2.

Item	Description	Notes
Typo of analysis	Non-linear static analysis(elastic,contact)	!SOLUTION,TYPE=NLSTATIC !CONTACT
Number of nodes	408
Number of elements	168
Element type	Eight node hexahedral element	!ELEMENT,TYPE=361
Material name	MAT1	!MATERIAL,NAME=MAT1
Material property	ELASTIC	!ELASTIC
Boundary conditions	Restraint,Forced displacement
Matrix solution	CG/SSOR	!SOLVER,METHOD=CG,PRECOND=1

Shape of the analysis target

Fig. 4.9.1: Shape of the analysis target

Mesh data of the analysis target

Fig. 4.9.2: Mesh data of the analysis target

Analysis content

The extended Lagrangian multiplier method is used to perform a contact analysis in which a forced displacement in the compressive direction is applied to the upper surface of a 1/4 disc model. The analytical control data are shown below.

Analysis control data `cgs3.cnt`.

#  Control File for FISTR
## Analysis Control
!VERSION
 3
!SOLUTION, TYPE=NLSTATIC
!WRITE,RESULT
!WRITE,VISUAL
## Solver Control
### Boundary Conditon
!BOUNDARY, GRPID=1
 ALL, 3, 3, 0.0
 BOTTOM, 2, 2, 0.0
 CENTER, 1, 1, 0.0
 UPPER,  2, 2, -0.306
!CONTACT_ALGO, TYPE=ALAGRANGE
!CONTACT, GRPID=1
 CP1, 0.0
### STEP
!STEP, SUBSTEPS=5, CONVERG=1.0e-5
 BOUNDARY, 1
 CONTACT,  1
### Material
!MATERIAL, NAME=MAT1
!ELASTIC
 1100.0, 0.0
### Solver Setting
!SOLVER,METHOD=CG,PRECOND=1,ITERLOG=YES,TIMELOG=YES
 1000, 1
 1.0e-10, 1.0, 0.0
## Post Control
!VISUAL,metod=PSR
!surface_num=1
!surface 1
!output_type=VTK
!END

Analysis procedure

Execute the FrontISTR execution command fistr1.

$ cd FrontISTR/tutorial/09_contact_hertz
$ fistr1 -t 4
(Runs in 4 threads.)

Analysis results

The results of the 5th substep are shown in Figure 4.9.3. A deformation diagram with contours of the y-direction displacement is created by REVOCAP_PrePost. A part of the analysis results log file is shown below as numerical data for the analysis results.

Analysis results of deformation and y-direction displacement

Fig. 4.9.3: Analysis results of deformation and y-direction displacement

Analysis results log `0.log`.

 fstr_setup: OK
#### Result step=     0
 ##### Local Summary @Node    :Max/IdMax/Min/IdMin####
 //U1    0.0000E+00         1  0.0000E+00         1
 //U2    0.0000E+00         1  0.0000E+00         1
 //U3    0.0000E+00         1  0.0000E+00         1
 //E11   0.0000E+00         1  0.0000E+00         1
 //E22   0.0000E+00         1  0.0000E+00         1
 //E33   0.0000E+00         1  0.0000E+00         1
 //E12   0.0000E+00         1  0.0000E+00         1
 //E23   0.0000E+00         1  0.0000E+00         1
 //E31   0.0000E+00         1  0.0000E+00         1
 //S11   0.0000E+00         1  0.0000E+00         1
 //S22   0.0000E+00         1  0.0000E+00         1
 //S33   0.0000E+00         1  0.0000E+00         1
 //S12   0.0000E+00         1  0.0000E+00         1
 //S23   0.0000E+00         1  0.0000E+00         1
 //S31   0.0000E+00         1  0.0000E+00         1
 //SMS   0.0000E+00         1  0.0000E+00         1
 ##### Local Summary @Element :Max/IdMax/Min/IdMin####
 //E11   0.0000E+00         1  0.0000E+00         1
 //E22   0.0000E+00         1  0.0000E+00         1

Contact Analysis (Part 1)