Hi ,
I would like to expose one issue that a new ccx user has suffer with thermal transient. I’m using a simpler case scenario to explain it.
Test T3 from NAFEMS publication TNSB, Rev. 3, “The Standard NAFEMS Benchmarks,” October 1990.
Expected value at t=32s is T=36.6ºC at a distance of 0.2m to the hot side.
When no iteration scheme is provided, ccx Default uses a time period of 1 and a maximum time step of 1.e+30 (Abaqus uses a value of 1) as default value.
That means it will try to solve it with time increments as large as possible. From my point of view this approach could be improved, especially in transient thermal analysis.
The problem is that, as in this NAFEM Test, there might be an amplitude card with time varying temperature. In that case, I consider default values should be related to
1-The time period in the *Amplitude card.
2- The time step discretization used in the *Amplitude card.
If not, the result is far from the right solution and Default settings don’t help the user.
**
** Heading +++++++++++++++++++++++++++++++++++++++++++++++++
**
*Heading
Hash: WXGjPLYz, Date: 12/03/2023, Unit system: M_KG_S_C
**
** Nodes +++++++++++++++++++++++++++++++++++++++++++++++++++
**
*Node
1, 0.00000000E+000, 0.00000000E+000, 0.00000000E+000
2, 1.00000000E-002, 0.00000000E+000, 0.00000000E+000
3, 1.00000000E-002, 1.00000000E-002, 0.00000000E+000
4, 0.00000000E+000, 1.00000000E-002, 0.00000000E+000
5, 0.00000000E+000, 0.00000000E+000, 1.00000000E-001
6, 1.00000000E-002, 0.00000000E+000, 1.00000000E-001
7, 1.00000000E-002, 1.00000000E-002, 1.00000000E-001
8, 0.00000000E+000, 1.00000000E-002, 1.00000000E-001
9, 0.00000000E+000, 0.00000000E+000, 2.00000000E-002
10, 0.00000000E+000, 0.00000000E+000, 4.00000000E-002
11, 0.00000000E+000, 0.00000000E+000, 6.00000000E-002
12, 0.00000000E+000, 0.00000000E+000, 8.00000000E-002
13, 0.00000000E+000, 1.00000000E-002, 2.00000000E-002
14, 0.00000000E+000, 1.00000000E-002, 4.00000000E-002
15, 0.00000000E+000, 1.00000000E-002, 6.00000000E-002
16, 0.00000000E+000, 1.00000000E-002, 8.00000000E-002
17, 1.00000000E-002, 0.00000000E+000, 2.00000000E-002
18, 1.00000000E-002, 0.00000000E+000, 4.00000000E-002
19, 1.00000000E-002, 0.00000000E+000, 6.00000000E-002
20, 1.00000000E-002, 0.00000000E+000, 8.00000000E-002
21, 1.00000000E-002, 1.00000000E-002, 2.00000000E-002
22, 1.00000000E-002, 1.00000000E-002, 4.00000000E-002
23, 1.00000000E-002, 1.00000000E-002, 6.00000000E-002
24, 1.00000000E-002, 1.00000000E-002, 8.00000000E-002
25, 5.00000000E-003, 0.00000000E+000, 8.00000000E-002
26, 1.00000000E-002, 5.00000000E-003, 8.00000000E-002
27, 5.00000000E-003, 1.00000000E-002, 8.00000000E-002
28, 0.00000000E+000, 5.00000000E-003, 8.00000000E-002
29, 0.00000000E+000, 0.00000000E+000, 9.00000000E-002
30, 1.00000000E-002, 0.00000000E+000, 9.00000000E-002
31, 1.00000000E-002, 1.00000000E-002, 9.00000000E-002
32, 0.00000000E+000, 1.00000000E-002, 9.00000000E-002
33, 5.00000000E-003, 0.00000000E+000, 1.00000000E-001
34, 1.00000000E-002, 5.00000000E-003, 1.00000000E-001
35, 5.00000000E-003, 1.00000000E-002, 1.00000000E-001
36, 0.00000000E+000, 5.00000000E-003, 1.00000000E-001
37, 5.00000000E-003, 0.00000000E+000, 0.00000000E+000
38, 1.00000000E-002, 5.00000000E-003, 0.00000000E+000
39, 5.00000000E-003, 1.00000000E-002, 0.00000000E+000
40, 0.00000000E+000, 5.00000000E-003, 0.00000000E+000
41, 0.00000000E+000, 0.00000000E+000, 1.00000000E-002
42, 1.00000000E-002, 0.00000000E+000, 1.00000000E-002
43, 1.00000000E-002, 1.00000000E-002, 1.00000000E-002
44, 0.00000000E+000, 1.00000000E-002, 1.00000000E-002
45, 5.00000000E-003, 0.00000000E+000, 2.00000000E-002
46, 1.00000000E-002, 5.00000000E-003, 2.00000000E-002
47, 5.00000000E-003, 1.00000000E-002, 2.00000000E-002
48, 0.00000000E+000, 5.00000000E-003, 2.00000000E-002
49, 0.00000000E+000, 0.00000000E+000, 3.00000000E-002
50, 1.00000000E-002, 0.00000000E+000, 3.00000000E-002
51, 1.00000000E-002, 1.00000000E-002, 3.00000000E-002
52, 0.00000000E+000, 1.00000000E-002, 3.00000000E-002
53, 5.00000000E-003, 0.00000000E+000, 4.00000000E-002
54, 1.00000000E-002, 5.00000000E-003, 4.00000000E-002
55, 5.00000000E-003, 1.00000000E-002, 4.00000000E-002
56, 0.00000000E+000, 5.00000000E-003, 4.00000000E-002
57, 0.00000000E+000, 0.00000000E+000, 5.00000000E-002
58, 1.00000000E-002, 0.00000000E+000, 5.00000000E-002
59, 1.00000000E-002, 1.00000000E-002, 5.00000000E-002
60, 0.00000000E+000, 1.00000000E-002, 5.00000000E-002
61, 5.00000000E-003, 0.00000000E+000, 6.00000000E-002
62, 1.00000000E-002, 5.00000000E-003, 6.00000000E-002
63, 5.00000000E-003, 1.00000000E-002, 6.00000000E-002
64, 0.00000000E+000, 5.00000000E-003, 6.00000000E-002
65, 0.00000000E+000, 0.00000000E+000, 7.00000000E-002
66, 1.00000000E-002, 0.00000000E+000, 7.00000000E-002
67, 1.00000000E-002, 1.00000000E-002, 7.00000000E-002
68, 0.00000000E+000, 1.00000000E-002, 7.00000000E-002
**
** Elements ++++++++++++++++++++++++++++++++++++++++++++++++
**
*Element, Type=C3D20R, Elset=Solid_part-1
1, 12, 20, 24, 16, 5, 6, 7, 8, 25, 26, 27, 28, 33, 34, 35,
36, 29, 30, 31, 32
2, 1, 2, 3, 4, 9, 17, 21, 13, 37, 38, 39, 40, 45, 46, 47,
48, 41, 42, 43, 44
3, 9, 17, 21, 13, 10, 18, 22, 14, 45, 46, 47, 48, 53, 54, 55,
56, 49, 50, 51, 52
4, 10, 18, 22, 14, 11, 19, 23, 15, 53, 54, 55, 56, 61, 62, 63,
64, 57, 58, 59, 60
5, 11, 19, 23, 15, 12, 20, 24, 16, 61, 62, 63, 64, 25, 26, 27,
28, 65, 66, 67, 68
**
** Node sets +++++++++++++++++++++++++++++++++++++++++++++++
**
*Nset, Nset=Internal_Selection-1_Temperature-1
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
65, 66, 67, 68
*Nset, Nset=Internal_Selection-2_Temperature-1
5, 6, 7, 8, 33, 34, 35, 36
*Nset, Nset=Internal_Selection-1_Temperature-2
1, 2, 3, 4, 37, 38, 39, 40
**
** Element sets ++++++++++++++++++++++++++++++++++++++++++++
**
*Elset, Elset=Missing_section-1
1, 2, 3, 4, 5
*Elset, Elset=Internal_Selection-1_Solid_Section-1
Solid_part-1
**
** Surfaces ++++++++++++++++++++++++++++++++++++++++++++++++
**
**
** Physical constants ++++++++++++++++++++++++++++++++++++++
**
**
** Materials +++++++++++++++++++++++++++++++++++++++++++++++
**
*Material, Name=Material-1
*Density
7200
*Elastic
210000000, 0
*Conductivity
35
*Specific heat
440.5
**
** Sections ++++++++++++++++++++++++++++++++++++++++++++++++
**
*Solid section, Elset=Internal_Selection-1_Solid_Section-1, Material=Material-1
**
** Pre-tension sections ++++++++++++++++++++++++++++++++++++
**
**
** Constraints +++++++++++++++++++++++++++++++++++++++++++++
**
**
** Surface interactions ++++++++++++++++++++++++++++++++++++
**
**
** Contact pairs +++++++++++++++++++++++++++++++++++++++++++
**
**
** Amplitudes ++++++++++++++++++++++++++++++++++++++++++++++
**
*Amplitude, Name=T3_NAFEMS_TNSB-0-32
0, 0, 0.1, 0.785390089, 0.2, 1.570731731, 0.3, 2.355976483,
0.4, 3.141075908, 0.5, 3.925981576, 0.6, 4.710645071, 0.7, 5.495017991,
0.8, 6.279051953, 0.9, 7.062698593, 1, 7.845909573, 1.1, 8.62863658,
1.2, 9.410831332, 1.3, 10.19244558, 1.4, 10.97343111, 1.5, 11.75373975,
1.6, 12.53332336, 1.7, 13.31213385, 1.8, 14.09012319, 1.9, 14.86724339,
2, 15.6434465, 2.1, 16.41868466, 2.2, 17.19291003, 2.3, 17.96607486,
2.4, 18.73813146, 2.5, 19.5090322, 2.6, 20.27872954, 2.7, 21.04717598,
2.8, 21.81432414, 2.9, 22.58012669, 3, 23.34453639, 3.1, 24.10750608,
3.2, 24.86898872, 3.3, 25.62893731, 3.4, 26.387305, 3.5, 27.14404499,
3.6, 27.8991106, 3.7, 28.65245527, 3.8, 29.40403252, 3.9, 30.15379599,
4, 30.90169944, 4.1, 31.64769672, 4.2, 32.39174182, 4.3, 33.13378885,
4.4, 33.87379202, 4.5, 34.61170571, 4.6, 35.34748438, 4.7, 36.08108265,
4.8, 36.81245527, 4.9, 37.54155712, 5, 38.26834324, 5.1, 38.99276878,
5.2, 39.71478906, 5.3, 40.43435955, 5.4, 41.15143586, 5.5, 41.86597375,
5.6, 42.57792916, 5.7, 43.28725815, 5.8, 43.99391699, 5.9, 44.69786207,
6, 45.39904997, 6.1, 46.09743745, 6.2, 46.79298143, 6.3, 47.48563899,
6.4, 48.17536741, 6.5, 48.86212415, 6.6, 49.54586684, 6.7, 50.22655331,
6.8, 50.90414158, 6.9, 51.57858983, 7, 52.24985647, 7.1, 52.9179001,
7.2, 53.5826795, 7.3, 54.24415367, 7.4, 54.9022818, 7.5, 55.5570233,
7.6, 56.20833779, 7.7, 56.85618507, 7.8, 57.5005252, 7.9, 58.14131843,
8, 58.77852523, 8.1, 59.41210629, 8.2, 60.04202253, 8.3, 60.6682351,
8.4, 61.29070537, 8.5, 61.90939493, 8.6, 62.52426563, 8.7, 63.13527954,
8.8, 63.74239897, 8.9, 64.34558647, 9, 64.94480483, 9.1, 65.54001709,
9.2, 66.13118653, 9.3, 66.71827669, 9.4, 67.30125135, 9.5, 67.88007455,
9.6, 68.45471059, 9.7, 69.02512402, 9.8, 69.59127966, 9.9, 70.15314258,
10, 70.71067812, 10.1, 71.26385189, 10.2, 71.81262978, 10.3, 72.35697792,
10.4, 72.89686274, 10.5, 73.43225094, 10.6, 73.9631095, 10.7, 74.48940566,
10.8, 75.01110696, 10.9, 75.52818123, 11, 76.04059656, 11.1, 76.54832135,
11.2, 77.05132428, 11.3, 77.54957432, 11.4, 78.04304073, 11.5, 78.53169309,
11.6, 79.01550124, 11.7, 79.49443534, 11.8, 79.96846585, 11.9, 80.43756353,
12, 80.90169944, 12.1, 81.36084495, 12.2, 81.81497174, 12.3, 82.2640518,
12.4, 82.70805743, 12.5, 83.14696123, 12.6, 83.58073614, 12.7, 84.00935539,
12.8, 84.43279255, 12.9, 84.8510215, 13, 85.26401644, 13.1, 85.67175189,
13.2, 86.0742027, 13.3, 86.47134405, 13.4, 86.86315144, 13.5, 87.24960071,
13.6, 87.630668, 13.7, 88.00632983, 13.8, 88.37656301, 13.9, 88.74134471,
14, 89.10065242, 14.1, 89.45446398, 14.2, 89.80275758, 14.3, 90.14551171,
14.4, 90.48270525, 14.5, 90.81431738, 14.6, 91.14032766, 14.7, 91.46071598,
14.8, 91.77546257, 14.9, 92.08454801, 15, 92.38795325, 15.1, 92.68565956,
15.2, 92.97764859, 15.3, 93.26390231, 15.4, 93.54440308, 15.5, 93.81913359,
15.6, 94.0880769, 15.7, 94.3512164, 15.8, 94.60853588, 15.9, 94.86001946,
16, 95.10565163, 16.1, 95.34541723, 16.2, 95.57930148, 16.3, 95.80728995,
16.4, 96.02936857, 16.5, 96.24552365, 16.6, 96.45574185, 16.7, 96.6600102,
16.8, 96.85831611, 16.9, 97.05064735, 17, 97.23699204, 17.1, 97.4173387,
17.2, 97.59167619, 17.3, 97.75999378, 17.4, 97.92228106, 17.5, 98.07852804,
17.6, 98.22872507, 17.7, 98.37286289, 17.8, 98.51093262, 17.9, 98.64292572,
18, 98.76883406, 18.1, 98.88864987, 18.2, 99.00236577, 18.3, 99.10997474,
18.4, 99.21147013, 18.5, 99.3068457, 18.6, 99.39609555, 18.7, 99.47921418,
18.8, 99.55619646, 18.9, 99.62703765, 19, 99.69173337, 19.1, 99.75027964,
19.2, 99.80267284, 19.3, 99.84890975, 19.4, 99.8889875, 19.5, 99.92290362,
19.6, 99.95065604, 19.7, 99.97224302, 19.8, 99.98766325, 19.9, 99.99691576,
20, 100, 20.1, 99.99691576, 20.2, 99.98766325, 20.3, 99.97224302,
20.4, 99.95065604, 20.5, 99.92290362, 20.6, 99.8889875, 20.7, 99.84890975,
20.8, 99.80267284, 20.9, 99.75027964, 21, 99.69173337, 21.1, 99.62703765,
21.2, 99.55619646, 21.3, 99.47921418, 21.4, 99.39609555, 21.5, 99.3068457,
21.6, 99.21147013, 21.7, 99.10997474, 21.8, 99.00236577, 21.9, 98.88864987,
22, 98.76883406, 22.1, 98.64292572, 22.2, 98.51093262, 22.3, 98.37286289,
22.4, 98.22872507, 22.5, 98.07852804, 22.6, 97.92228106, 22.7, 97.75999378,
22.8, 97.59167619, 22.9, 97.4173387, 23, 97.23699204, 23.1, 97.05064735,
23.2, 96.85831611, 23.3, 96.6600102, 23.4, 96.45574185, 23.5, 96.24552365,
23.6, 96.02936857, 23.7, 95.80728995, 23.8, 95.57930148, 23.9, 95.34541723,
24, 95.10565163, 24.1, 94.86001946, 24.2, 94.60853588, 24.3, 94.3512164,
24.4, 94.0880769, 24.5, 93.81913359, 24.6, 93.54440308, 24.7, 93.26390231,
24.8, 92.97764859, 24.9, 92.68565956, 25, 92.38795325, 25.1, 92.08454801,
25.2, 91.77546257, 25.3, 91.46071598, 25.4, 91.14032766, 25.5, 90.81431738,
25.6, 90.48270525, 25.7, 90.14551171, 25.8, 89.80275758, 25.9, 89.45446398,
26, 89.10065242, 26.1, 88.74134471, 26.2, 88.37656301, 26.3, 88.00632983,
26.4, 87.630668, 26.5, 87.24960071, 26.6, 86.86315144, 26.7, 86.47134405,
26.8, 86.0742027, 26.9, 85.67175189, 27, 85.26401644, 27.1, 84.8510215,
27.2, 84.43279255, 27.3, 84.00935539, 27.4, 83.58073614, 27.5, 83.14696123,
27.6, 82.70805743, 27.7, 82.2640518, 27.8, 81.81497174, 27.9, 81.36084495,
28, 80.90169944, 28.1, 80.43756353, 28.2, 79.96846585, 28.3, 79.49443534,
28.4, 79.01550124, 28.5, 78.53169309, 28.6, 78.04304073, 28.7, 77.54957432,
28.8, 77.05132428, 28.9, 76.54832135, 29, 76.04059656, 29.1, 75.52818123,
29.2, 75.01110696, 29.3, 74.48940566, 29.4, 73.9631095, 29.5, 73.43225094,
29.6, 72.89686274, 29.7, 72.35697792, 29.8, 71.81262978, 29.9, 71.26385189,
30, 70.71067812, 30.1, 70.15314258, 30.2, 69.59127966, 30.3, 69.02512402,
30.4, 68.45471059, 30.5, 67.88007455, 30.6, 67.30125135, 30.7, 66.71827669,
30.8, 66.13118653, 30.9, 65.54001709, 31, 64.94480483, 31.1, 64.34558647,
31.2, 63.74239897, 31.3, 63.13527954, 31.4, 62.52426563, 31.5, 61.90939493,
31.6, 61.29070537, 31.7, 60.6682351, 31.8, 60.04202253, 31.9, 59.41210629,
32, 58.77852523
*Amplitude, Name=T3_NAFEMS_TNSB_0-1
0, 0, 0.031, 7.846, 0.063, 15.643, 0.094, 23.345,
0.125, 30.902, 0.156, 38.268, 0.188, 45.399, 0.219, 52.25,
0.25, 58.779, 0.281, 64.945, 0.313, 70.711, 0.344, 76.041,
0.375, 80.902, 0.406, 85.264, 0.438, 89.101, 0.469, 92.388,
0.5, 95.106, 0.531, 97.237, 0.563, 98.769, 0.594, 99.692,
0.625, 100, 0.656, 99.692, 0.688, 98.769, 0.719, 97.237,
0.75, 95.106, 0.781, 92.388, 0.813, 89.101, 0.844, 85.264,
0.875, 80.902, 0.906, 76.041, 0.938, 70.711, 0.969, 64.945,
1, 58.779
**
** Initial conditions ++++++++++++++++++++++++++++++++++++++
**
** Name: Temperature-1
*Initial conditions, Type=Temperature
Internal_Selection-1_Temperature-1, 0
**
** Steps +++++++++++++++++++++++++++++++++++++++++++++++++++
**
**
** Default +++++++++++++++++++++++++++++++++++++++++++++++++
**
*Step
*Heat transfer, Solver=Pardiso
**
** Output frequency ++++++++++++++++++++++++++++++++++++++++
**
*Output, Frequency=1
**
** Boundary conditions +++++++++++++++++++++++++++++++++++++
**
*Boundary, op=New
** Name: Temperature-1
*Boundary
Internal_Selection-2_Temperature-1, 11, 11, 0
** Name: Temperature-2
*Boundary, Amplitude=T3_NAFEMS_TNSB_0-1
Internal_Selection-1_Temperature-2, 11, 11, 1
**
** Loads +++++++++++++++++++++++++++++++++++++++++++++++++++
**
*Cflux, op=New
**
** Defined fields ++++++++++++++++++++++++++++++++++++++++++
**
**
** History outputs +++++++++++++++++++++++++++++++++++++++++
**
**
** Field outputs +++++++++++++++++++++++++++++++++++++++++++
**
*Node file
NT, RFL
*El file
HFL
**
** End step ++++++++++++++++++++++++++++++++++++++++++++++++
**
*End step
**
** Automatic-OK ++++++++++++++++++++++++++++++++++++++++++++
**
** Name: Automatic-OK: Deactivated
** Name: CaeModel.HeatTransferStep: Deactivated
**
** Boundary conditions +++++++++++++++++++++++++++++++++++++
**
** Name: Temperature-1: Deactivated
** Name: Temperature-2: Deactivated
**
** Loads +++++++++++++++++++++++++++++++++++++++++++++++++++
**
**
** Defined fields ++++++++++++++++++++++++++++++++++++++++++
**
**
** History outputs +++++++++++++++++++++++++++++++++++++++++
**
**
** Field outputs +++++++++++++++++++++++++++++++++++++++++++
**
** Name: NF-Output-1: Deactivated
** Name: EF-Output-1: Deactivated
**
** End step ++++++++++++++++++++++++++++++++++++++++++++++++
**
** Name: Automatic-OK: Deactivated