Non-linear Static Analysis (Hyperelasticity, Part 2)¶
This analysis uses the data of tutorial/04_hyperelastic_spring.
Analysis target¶
The spring is the object of the analysis, the geometry is shown in Figure 4.4.1 and the mesh data is shown in Figure 4.4.2.
| Item | Description | Notes | Reference |
|---|---|---|---|
| Type of analysis | Nonlinear static analysis (hyperelasticity) | !SOLUTION,TYPE=NLSTATIC | |
| Number of nodes | 78,771 | ||
| Number of elements | 46,454 | ||
| Element type | Ten node tetrahedral quadratic element | !ELEMENT,TYPE=342 | |
| Material name | MAT1 | !MATERIAL,NAME=MAT1 | |
| Material property | HYPERELASTIC | !HYPERELASTIC,TYPE=ARRUDA-BOYCE | |
| Boundary conditions | Restraint / prescribed displacement | ||
| Matrix solution | CG/SSOR | !SOLVER,METHOD=CG,PRECOND=1 |


Analysis content¶
A stress analysis is performed by constraining the displacement of the constrained surface shown in Figure 4.4.1 and applying a prescribed displacement to the prescribed-displacement surface. The Arruda-Boyce model is used for the hyperelastic material constitutive law. The analysis control data are shown below.
Analysis control data spring.cnt¶
# Control File for FISTR
## Analysis Control
!VERSION
3
!SOLUTION, TYPE=NLSTATIC
!WRITE,RESULT
!WRITE,VISUAL
## Solver Control
### Boundary Conditon
!BOUNDARY, GRPID=1
LOADS, 2, 2, -5.0
FIX, 1, 3, 0.0
### STEP
!STEP, SUBSTEPS=1, CONVERG=1.0e-5
BOUNDARY, 1
### Material
!MATERIAL, NAME=MAT1
!HYPERELASTIC, TYPE=ARRUDA-BOYCE
0.71, 1.7029, 0.1408
### Solver Setting
!SOLVER,METHOD=CG,PRECOND=1,ITERLOG=YES,TIMELOG=YES
10000, 1
1.0e-8, 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.
(Runs in 4 threads.)
Analysis results¶
A deformation diagram with a contoured displacement is created by REVOCAP_PrePost and shown in Figure 4.4.3. A part of the log file is shown below as numerical data for the analysis results.

Log file 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
//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
##### Global 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
##### Global Summary @Element :Max/IdMax/Min/IdMin####
//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
#### Result step= 1
##### Local Summary @Node :Max/IdMax/Min/IdMin####
//U1 2.6070E-01 42179 -2.4651E-01 44163
//U2 2.0567E-02 14512 -5.0036E+00 44753
//U3 6.6559E-02 15443 -6.6862E-01 44664
//E11 4.1026E-03 1015 -4.5809E-03 3429
//E22 2.3030E-03 42626 -1.5152E-03 44761
//E33 4.1949E-03 23553 -5.0169E-03 27938
//E12 1.3348E-02 55149 -1.3381E-02 56829
//E23 2.7881E-02 48353 -1.9534E-02 48322
//E31 1.0861E-02 47938 -8.8803E-03 9493
//S11 8.4247E-03 8264 -9.1017E-03 8501
//S22 1.0769E-02 56772 -6.3921E-03 56787
//S33 1.3881E-02 56764 -1.2778E-02 42632
//S12 1.2396E-02 55149 -1.2434E-02 56829
//S23 2.5880E-02 48353 -1.8138E-02 48322
//S31 1.0081E-02 47938 -8.2435E-03 9493
//SMS 4.9638E-02 48353 2.8482E-04 66578
##### Local Summary @Element :Max/IdMax/Min/IdMin####
//E11 3.9156E-03 34074 -4.3403E-03 16932
//E22 1.8391E-03 23282 -1.2721E-03 56220
//E33 3.9490E-03 45925 -4.4530E-03 34145
//E12 1.2578E-02 45680 -1.1729E-02 19492
//E23 2.0534E-02 40739 -1.3512E-02 24172
//E31 9.4162E-03 32786 -7.6149E-03 44971
//S11 7.7882E-03 25880 -8.2932E-03 45925
//S22 6.8884E-03 23275 -6.1373E-03 49821
//S33 9.9242E-03 59974 -9.5475E-03 31626
//S12 1.1679E-02 45680 -1.0893E-02 19492
//S23 1.9071E-02 40739 -1.2534E-02 24172
//S31 8.7376E-03 32786 -7.0660E-03 44971
//SMS 3.5586E-02 40739 4.1161E-04 40537
##### Global Summary @Node :Max/IdMax/Min/IdMin####
//U1 2.6070E-01 42179 -2.4651E-01 44163
//U2 2.0567E-02 14512 -5.0036E+00 44753
//U3 6.6559E-02 15443 -6.6862E-01 44664
//E11 4.1026E-03 1015 -4.5809E-03 3429
//E22 2.3030E-03 42626 -1.5152E-03 44761
//E33 4.1949E-03 23553 -5.0169E-03 27938
//E12 1.3348E-02 55149 -1.3381E-02 56829
//E23 2.7881E-02 48353 -1.9534E-02 48322
//E31 1.0861E-02 47938 -8.8803E-03 9493
//S11 8.4247E-03 8264 -9.1017E-03 8501
//S22 1.0769E-02 56772 -6.3921E-03 56787
//S33 1.3881E-02 56764 -1.2778E-02 42632
//S12 1.2396E-02 55149 -1.2434E-02 56829
//S23 2.5880E-02 48353 -1.8138E-02 48322
//S31 1.0081E-02 47938 -8.2435E-03 9493
//SMS 4.9638E-02 48353 2.8482E-04 66578
##### Global Summary @Element :Max/IdMax/Min/IdMin####
//E11 3.9156E-03 34074 -4.3403E-03 16932
//E22 1.8391E-03 23282 -1.2721E-03 56220
//E33 3.9490E-03 45925 -4.4530E-03 34145
//E12 1.2578E-02 45680 -1.1729E-02 19492
//E23 2.0534E-02 40739 -1.3512E-02 24172
//E31 9.4162E-03 32786 -7.6149E-03 44971
//S11 7.7882E-03 25880 -8.2932E-03 45925
//S22 6.8884E-03 23275 -6.1373E-03 49821
//S33 9.9242E-03 59974 -9.5475E-03 31626
//S12 1.1679E-02 45680 -1.0893E-02 19492
//S23 1.9071E-02 40739 -1.2534E-02 24172
//S31 8.7376E-03 32786 -7.0660E-03 44971
//SMS 3.5586E-02 40739 4.1161E-04 40537