*Model Change with elements that are part of a contact

febing · October 17, 2023, 9:09am

Hello,
is it posibble to remove/add elements with *Model Change, that have surfaces that are part in a contact definition?
When i do that, calculix seems to crash.

Calc_em · October 17, 2023, 11:30am

Try this (from Abaqus documentation):

If elements that are connected to a contact pair are removed, the contact pair should also be removed to avoid solver problems.

febing · October 17, 2023, 11:53am

Hello Calc_em,

i tried this. I removed the contact, befor i removed the element set.
But calculix does not like it either.

Calc_em · October 18, 2023, 7:46am

Try testing this on a simplified model (reduced as much as possible - to just a few elements) and share it here.

febing · October 18, 2023, 8:11pm

Here is a sample input:

** Heading +++++++++++++++++++++++++++++++++++++++++++++++++
**
*Heading
Hash: LsCkcVm2, Date: 10/18/2023, Unit system: MM_TON_S_C
**
** Nodes +++++++++++++++++++++++++++++++++++++++++++++++++++
**
*Node
1, 0.00000000E+000, 0.00000000E+000, 1.00000000E+001
2, 0.00000000E+000, 0.00000000E+000, 2.00000000E+001
3, 0.00000000E+000, 1.00000000E+001, 1.00000000E+001
4, 0.00000000E+000, 1.00000000E+001, 2.00000000E+001
5, 1.00000000E+001, 0.00000000E+000, 1.00000000E+001
6, 1.00000000E+001, 0.00000000E+000, 2.00000000E+001
7, 1.00000000E+001, 1.00000000E+001, 1.00000000E+001
8, 1.00000000E+001, 1.00000000E+001, 2.00000000E+001
9, 0.00000000E+000, 0.00000000E+000, 1.50000000E+001
10, 0.00000000E+000, 5.00000000E+000, 2.00000000E+001
11, 0.00000000E+000, 5.00000000E+000, 1.50000000E+001
12, 0.00000000E+000, 5.00000000E+000, 1.00000000E+001
13, 0.00000000E+000, 1.00000000E+001, 1.50000000E+001
14, 1.00000000E+001, 0.00000000E+000, 1.50000000E+001
15, 1.00000000E+001, 5.00000000E+000, 1.00000000E+001
16, 1.00000000E+001, 5.00000000E+000, 1.50000000E+001
17, 1.00000000E+001, 1.00000000E+001, 1.50000000E+001
18, 1.00000000E+001, 5.00000000E+000, 2.00000000E+001
19, 5.00000000E+000, 0.00000000E+000, 1.00000000E+001
20, 5.00000000E+000, 0.00000000E+000, 1.50000000E+001
21, 5.00000000E+000, 0.00000000E+000, 2.00000000E+001
22, 5.00000000E+000, 1.00000000E+001, 1.00000000E+001
23, 5.00000000E+000, 1.00000000E+001, 1.50000000E+001
24, 5.00000000E+000, 1.00000000E+001, 2.00000000E+001
25, 5.00000000E+000, 5.00000000E+000, 1.00000000E+001
26, 5.00000000E+000, 5.00000000E+000, 2.00000000E+001
27, 0.00000000E+000, 0.00000000E+000, 0.00000000E+000
28, 0.00000000E+000, 0.00000000E+000, 1.00000000E+001
29, 0.00000000E+000, 1.00000000E+001, 0.00000000E+000
30, 0.00000000E+000, 1.00000000E+001, 1.00000000E+001
31, 1.00000000E+001, 0.00000000E+000, 0.00000000E+000
32, 1.00000000E+001, 0.00000000E+000, 1.00000000E+001
33, 1.00000000E+001, 1.00000000E+001, 0.00000000E+000
34, 1.00000000E+001, 1.00000000E+001, 1.00000000E+001
35, 0.00000000E+000, 0.00000000E+000, 5.00000000E+000
36, 0.00000000E+000, 5.00000000E+000, 1.00000000E+001
37, 0.00000000E+000, 5.00000000E+000, 5.00000000E+000
38, 0.00000000E+000, 5.00000000E+000, 0.00000000E+000
39, 0.00000000E+000, 1.00000000E+001, 5.00000000E+000
40, 1.00000000E+001, 0.00000000E+000, 5.00000000E+000
41, 1.00000000E+001, 5.00000000E+000, 0.00000000E+000
42, 1.00000000E+001, 5.00000000E+000, 5.00000000E+000
43, 1.00000000E+001, 1.00000000E+001, 5.00000000E+000
44, 1.00000000E+001, 5.00000000E+000, 1.00000000E+001
45, 5.00000000E+000, 0.00000000E+000, 0.00000000E+000
46, 5.00000000E+000, 0.00000000E+000, 5.00000000E+000
47, 5.00000000E+000, 0.00000000E+000, 1.00000000E+001
48, 5.00000000E+000, 1.00000000E+001, 0.00000000E+000
49, 5.00000000E+000, 1.00000000E+001, 5.00000000E+000
50, 5.00000000E+000, 1.00000000E+001, 1.00000000E+001
51, 5.00000000E+000, 5.00000000E+000, 0.00000000E+000
52, 5.00000000E+000, 5.00000000E+000, 1.00000000E+001
**
** Elements ++++++++++++++++++++++++++++++++++++++++++++++++
**
*Element, Type=C3D10, Elset=Solid_part-1
1, 4, 6, 7, 8, 26, 16, 23, 24, 18, 17
2, 6, 4, 7, 1, 26, 23, 16, 20, 11, 25
3, 7, 1, 4, 3, 25, 11, 23, 22, 12, 13
4, 7, 1, 5, 6, 25, 19, 15, 16, 20, 14
5, 2, 1, 4, 6, 9, 11, 10, 21, 20, 26
*Element, Type=C3D10, Elset=Solid_part-2
6, 30, 32, 33, 34, 52, 42, 49, 50, 44, 43
7, 32, 30, 33, 27, 52, 49, 42, 46, 37, 51
8, 33, 27, 30, 29, 51, 37, 49, 48, 38, 39
9, 33, 27, 31, 32, 51, 45, 41, 42, 46, 40
10, 28, 27, 30, 32, 35, 37, 36, 47, 46, 52
**
** Node sets +++++++++++++++++++++++++++++++++++++++++++++++
**
*Nset, Nset=Internal-1_master
1, 3, 5, 7, 12, 15, 19, 22, 25
*Nset, Nset=Internal-1_slave
28, 30, 32, 34, 36, 44, 47, 50, 52
*Nset, Nset=Internal_Selection-1_Fixed-1
27, 29, 31, 33, 38, 41, 45, 48, 51
**
** Element sets ++++++++++++++++++++++++++++++++++++++++++++
**
*Elset, Elset=Internal-1_master_S2
3
*Elset, Elset=Internal-1_master_S1
4
*Elset, Elset=Internal-1_slave_S2
6
*Elset, Elset=Internal-1_slave_S4
10
*Elset, Elset=Internal_Selection-1_Solid_Section-1
Solid_part-1,
Solid_part-2
*Elset, Elset=Internal_Selection-1_Gravity-1
Solid_part-1,
Solid_part-2
*Elset, Elset=Set-1
1, 2, 3, 4, 5
**
** Surfaces ++++++++++++++++++++++++++++++++++++++++++++++++
**
*Surface, Name=master, Type=Element
Internal-1_master_S2, S2
Internal-1_master_S1, S1
*Surface, Name=slave, Type=Element
Internal-1_slave_S2, S2
Internal-1_slave_S4, S4
**
** Physical constants ++++++++++++++++++++++++++++++++++++++
**
**
** Materials +++++++++++++++++++++++++++++++++++++++++++++++
**
*Material, Name=S235
*Density
7.8E-09
*Elastic
210000, 0.28
*Expansion, Zero=20
1.1E-05
*Conductivity
14
*Specific heat
440000000
**
** Sections ++++++++++++++++++++++++++++++++++++++++++++++++
**
*Solid section, Elset=Internal_Selection-1_Solid_Section-1, Material=S235
**
** Pre-tension sections ++++++++++++++++++++++++++++++++++++
**
**
** Constraints +++++++++++++++++++++++++++++++++++++++++++++
**
**
** Surface interactions ++++++++++++++++++++++++++++++++++++
**
*Surface interaction, Name=Surface_Interaction-1
*Surface behavior, Pressure-overclosure=Hard
*Friction
0.1
**
** Contact pairs +++++++++++++++++++++++++++++++++++++++++++
**
*Contact pair, Interaction=Surface_Interaction-1, Type=Surface to surface
slave, master
**
** Amplitudes ++++++++++++++++++++++++++++++++++++++++++++++
**
**
** Initial conditions ++++++++++++++++++++++++++++++++++++++
**
**
** Steps +++++++++++++++++++++++++++++++++++++++++++++++++++
**
**
** Step-1 ++++++++++++++++++++++++++++++++++++++++++++++++++
**
*Step, Inc=100
*Static
1, 1, 1E-05, 1E+30
**
** Output frequency ++++++++++++++++++++++++++++++++++++++++
**
*Output, Frequency=1
**
** Boundary conditions +++++++++++++++++++++++++++++++++++++
**
*Boundary, op=New
** Name: Fixed-1
*Boundary
Internal_Selection-1_Fixed-1, 1, 6, 0
**
** Loads +++++++++++++++++++++++++++++++++++++++++++++++++++
**
*Cload, op=New
*Dload, op=New
** Name: Gravity-1
*Dload
Internal_Selection-1_Gravity-1, Grav, 9810, 0, 0, -1
**
** Defined fields ++++++++++++++++++++++++++++++++++++++++++
**
**
** History outputs +++++++++++++++++++++++++++++++++++++++++
**
**
** Field outputs +++++++++++++++++++++++++++++++++++++++++++
**
*Node file
RF, U
*El file
S, E
*Model Change, Type=Contact Pair, Remove
master, slave
*Model Change, Type=Element, Remove
Set-1
**
** End step ++++++++++++++++++++++++++++++++++++++++++++++++
**
*End step

BM_PCC · January 22, 2024, 10:54am

Hello,

The *Model Change, Type=Contact Pair, Remove in Calculix inside the prepomax (windows) is not working.

I tried several times using different models, including the simplified model of @ [febing] but isn’t working.

The *Model Change, Type=Element, Remove works fine, but not the Contact Pair. The simulation just ends without errors.

Anyone had the same problem?

Best Regards

Calc_em · January 22, 2024, 12:33pm

The first thing is that the input above should be changed from:

to:

*Model Change, Type=Contact Pair, Remove
slave, master

Then it works in Abaqus but, for some reason, not in CalculiX.

Analysis with model change makes more sense when there are multiple steps so I propose something like this (again, works in Abaqus but not in CalculiX):

*Node
1, 0.00000000E+000, 0.00000000E+000, 1.00000000E+001
2, 0.00000000E+000, 0.00000000E+000, 2.00000000E+001
3, 0.00000000E+000, 1.00000000E+001, 1.00000000E+001
4, 0.00000000E+000, 1.00000000E+001, 2.00000000E+001
5, 1.00000000E+001, 0.00000000E+000, 1.00000000E+001
6, 1.00000000E+001, 0.00000000E+000, 2.00000000E+001
7, 1.00000000E+001, 1.00000000E+001, 1.00000000E+001
8, 1.00000000E+001, 1.00000000E+001, 2.00000000E+001
9, 0.00000000E+000, 0.00000000E+000, 1.50000000E+001
10, 0.00000000E+000, 5.00000000E+000, 2.00000000E+001
11, 0.00000000E+000, 5.00000000E+000, 1.50000000E+001
12, 0.00000000E+000, 5.00000000E+000, 1.00000000E+001
13, 0.00000000E+000, 1.00000000E+001, 1.50000000E+001
14, 1.00000000E+001, 0.00000000E+000, 1.50000000E+001
15, 1.00000000E+001, 5.00000000E+000, 1.00000000E+001
16, 1.00000000E+001, 5.00000000E+000, 1.50000000E+001
17, 1.00000000E+001, 1.00000000E+001, 1.50000000E+001
18, 1.00000000E+001, 5.00000000E+000, 2.00000000E+001
19, 5.00000000E+000, 0.00000000E+000, 1.00000000E+001
20, 5.00000000E+000, 0.00000000E+000, 1.50000000E+001
21, 5.00000000E+000, 0.00000000E+000, 2.00000000E+001
22, 5.00000000E+000, 1.00000000E+001, 1.00000000E+001
23, 5.00000000E+000, 1.00000000E+001, 1.50000000E+001
24, 5.00000000E+000, 1.00000000E+001, 2.00000000E+001
25, 5.00000000E+000, 5.00000000E+000, 1.00000000E+001
26, 5.00000000E+000, 5.00000000E+000, 2.00000000E+001
27, 0.00000000E+000, 0.00000000E+000, 0.00000000E+000
28, 0.00000000E+000, 0.00000000E+000, 1.00000000E+001
29, 0.00000000E+000, 1.00000000E+001, 0.00000000E+000
30, 0.00000000E+000, 1.00000000E+001, 1.00000000E+001
31, 1.00000000E+001, 0.00000000E+000, 0.00000000E+000
32, 1.00000000E+001, 0.00000000E+000, 1.00000000E+001
33, 1.00000000E+001, 1.00000000E+001, 0.00000000E+000
34, 1.00000000E+001, 1.00000000E+001, 1.00000000E+001
35, 0.00000000E+000, 0.00000000E+000, 5.00000000E+000
36, 0.00000000E+000, 5.00000000E+000, 1.00000000E+001
37, 0.00000000E+000, 5.00000000E+000, 5.00000000E+000
38, 0.00000000E+000, 5.00000000E+000, 0.00000000E+000
39, 0.00000000E+000, 1.00000000E+001, 5.00000000E+000
40, 1.00000000E+001, 0.00000000E+000, 5.00000000E+000
41, 1.00000000E+001, 5.00000000E+000, 0.00000000E+000
42, 1.00000000E+001, 5.00000000E+000, 5.00000000E+000
43, 1.00000000E+001, 1.00000000E+001, 5.00000000E+000
44, 1.00000000E+001, 5.00000000E+000, 1.00000000E+001
45, 5.00000000E+000, 0.00000000E+000, 0.00000000E+000
46, 5.00000000E+000, 0.00000000E+000, 5.00000000E+000
47, 5.00000000E+000, 0.00000000E+000, 1.00000000E+001
48, 5.00000000E+000, 1.00000000E+001, 0.00000000E+000
49, 5.00000000E+000, 1.00000000E+001, 5.00000000E+000
50, 5.00000000E+000, 1.00000000E+001, 1.00000000E+001
51, 5.00000000E+000, 5.00000000E+000, 0.00000000E+000
52, 5.00000000E+000, 5.00000000E+000, 1.00000000E+001
*Element, Type=C3D10, Elset=Solid_part-1
1, 4, 6, 7, 8, 26, 16, 23, 24, 18, 17
2, 6, 4, 7, 1, 26, 23, 16, 20, 11, 25
3, 7, 1, 4, 3, 25, 11, 23, 22, 12, 13
4, 7, 1, 5, 6, 25, 19, 15, 16, 20, 14
5, 2, 1, 4, 6, 9, 11, 10, 21, 20, 26
*Element, Type=C3D10, Elset=Solid_part-2
6, 30, 32, 33, 34, 52, 42, 49, 50, 44, 43
7, 32, 30, 33, 27, 52, 49, 42, 46, 37, 51
8, 33, 27, 30, 29, 51, 37, 49, 48, 38, 39
9, 33, 27, 31, 32, 51, 45, 41, 42, 46, 40
10, 28, 27, 30, 32, 35, 37, 36, 47, 46, 52
*Nset, Nset=Internal-1_master
1, 3, 5, 7, 12, 15, 19, 22, 25
*Nset, Nset=Internal-1_slave
28, 30, 32, 34, 36, 44, 47, 50, 52
*Nset, Nset=Internal_Selection-1_Fixed-1
27, 29, 31, 33, 38, 41, 45, 48, 51
*Elset, Elset=Internal-1_master_S2
3
*Elset, Elset=Internal-1_master_S1
4
*Elset, Elset=Internal-1_slave_S2
6
*Elset, Elset=Internal-1_slave_S4
10
*Elset, Elset=Internal_Selection-1_Solid_Section-1
Solid_part-1,
Solid_part-2
*Elset, Elset=Internal_Selection-1_Gravity-1
Solid_part-1,
Solid_part-2
*Elset, Elset=Set-1
1, 2, 3, 4, 5
*Surface, Name=master, Type=Element
Internal-1_master_S2, S2
Internal-1_master_S1, S1
*Surface, Name=slave, Type=Element
Internal-1_slave_S2, S2
Internal-1_slave_S4, S4
*Material, Name=S235
*Density
7.8E-09
*Elastic
210000, 0.28
*Solid section, Elset=Internal_Selection-1_Solid_Section-1, Material=S235
*Surface interaction, Name=Surface_Interaction-1
*Surface behavior, Pressure-overclosure=Hard
*Friction
0.1
*Contact pair, Interaction=Surface_Interaction-1, Type=Surface to surface
slave, master
*Step, Inc=100
*Static
1, 1, 1E-05, 1E+30
*Output, Frequency=1
*Boundary
Internal_Selection-1_Fixed-1, 1, 6, 0
*Dload
Internal_Selection-1_Gravity-1, Grav, 9810, 0, 0, -1
*Node file
RF, U
*El file
S, E
*End step
*Step, Inc=100
*Static
1, 1, 1E-05, 1E+30
*Output, Frequency=1
*Boundary
Internal_Selection-1_Fixed-1, 1, 6, 0
*Dload
Internal_Selection-1_Gravity-1, Grav, 9810, 0, 0, -1
*Node file
RF, U
*El file
S, E
*Model Change, Type=Contact Pair, Remove
slave, master
*Model Change, Type=Element, Remove
Set-1
*End step

Perhaps it’s a bug in CalculiX.

BM_PCC · January 23, 2024, 9:22am

@Calc_em I had the same experience.

Did you use calculix in prepomax(windows version) or your also tried in Linux?

Thanks for your feedback

Best Regards

Calc_em · January 23, 2024, 9:37am

I used standalone CalculiX (without PrePoMax) on Windows but it’s likely the same on Linux.

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