Creo Simulate contact analysis

[ilyachaban]

Hello, I'm trying to create and simulate contact analysis on mounted parts there are 6 main frames, 12 bolts and 4 pins with around 20 contacts defined. 

simulation doesn't converge at all. everything i've tried didn't get me anywhere always contact area is dancing around and residual factor too. 

I'm sure that I have defined all the contacts in all the places. All the frames are modelled as 1 part and all the bolts has slight interpenetration to create pretension. But it doesnt converge at all. 

Is there any good practice how to create contact simulation with many contacts? \

Things that i've tried: create pretension, delete pretension, fine mesh, rough mesh, change parameter called sim_contact_tolerance_factor increase/decreace, change convergence settings, finite friction, infinite friction, 0 friction, 

Example of convergence:

   Load factor            :     1.00000e-01
   Residual norm tolerance:     1.00000e-09

------------------------------------------
Iteration    Residual norm      Area
------------------------------------------
    1          1.0000e+00      7.0615e+04   Fri Feb 17, 2023   06:51:17
    2          1.0000e+00      4.5168e+05   Fri Feb 17, 2023   06:51:56
    3          1.0063e-03      3.4800e+05   Fri Feb 17, 2023   06:52:35
    4          1.3636e-06      2.9005e+05   Fri Feb 17, 2023   06:53:14
    5          1.5219e-07      2.6358e+05   Fri Feb 17, 2023   06:53:53
    6          7.2918e-07      2.1785e+05   Fri Feb 17, 2023   06:54:33
    7          3.9976e-08      1.8730e+05   Fri Feb 17, 2023   06:55:12
    8          2.2661e-08      1.7018e+05   Fri Feb 17, 2023   06:55:50
    9          1.0919e-08      1.7080e+05   Fri Feb 17, 2023   06:56:29
   10          5.4540e-09      1.6276e+05   Fri Feb 17, 2023   06:57:08
   11          3.2743e-09      1.5247e+05   Fri Feb 17, 2023   06:57:46
   12          4.0881e-09      1.4957e+05   Fri Feb 17, 2023   06:58:24
   13          6.8582e-05      1.8358e+05   Fri Feb 17, 2023   06:59:05
   14          1.0554e-08      1.7415e+05   Fri Feb 17, 2023   06:59:44
   15          4.1022e-07      1.5177e+05   Fri Feb 17, 2023   07:00:23
Loosening gap stiffness to improve convergence
   16          2.3832e-07      1.4155e+05   Fri Feb 17, 2023   07:01:02
   17          1.7176e-08      2.9714e+05   Fri Feb 17, 2023   07:01:41
   18          2.0151e-07      2.6400e+05   Fri Feb 17, 2023   07:02:20
   19          6.1776e-09      2.4227e+05   Fri Feb 17, 2023   07:02:59
   20          1.1068e-09      2.5557e+05   Fri Feb 17, 2023   07:03:41
   21          1.1850e-09      2.3187e+05   Fri Feb 17, 2023   07:04:23
   22          7.6003e-10      2.4082e+05   Fri Feb 17, 2023   07:05:05
Adjusted gap stiffness to prevent interpenetration
   23          2.7779e-08      2.2493e+05   Fri Feb 17, 2023   07:05:47
   24          3.6278e-09      2.1695e+05   Fri Feb 17, 2023   07:06:29
   25          3.0372e-09      2.0945e+05   Fri Feb 17, 2023   07:07:10
   26          9.6627e-10      2.1422e+05   Fri Feb 17, 2023   07:07:52
Adjusted gap stiffness to prevent interpenetration
   27          1.5556e-07      2.0513e+05   Fri Feb 17, 2023   07:08:34
   28          1.7384e-08      2.0158e+05   Fri Feb 17, 2023   07:09:16
   29          5.1700e-09      1.8797e+05   Fri Feb 17, 2023   07:09:58
   30          3.3820e-09      1.9962e+05   Fri Feb 17, 2023   07:10:37
   31          5.6008e-09      2.1553e+05   Fri Feb 17, 2023   07:11:20
   32          9.8902e-08      2.0151e+05   Fri Feb 17, 2023   07:12:02
   33          1.2410e-08      2.1347e+05   Fri Feb 17, 2023   07:12:44
   34          2.0315e-08      1.9927e+05   Fri Feb 17, 2023   07:13:29
   35          2.4502e-08      1.9847e+05   Fri Feb 17, 2023   07:14:14
   36          2.1911e-08      2.0351e+05   Fri Feb 17, 2023   07:14:56
   37          1.3892e-08      1.8761e+05   Fri Feb 17, 2023   07:15:38
   38          1.7767e-08      1.8462e+05   Fri Feb 17, 2023   07:16:23
   39          3.3594e-08      1.9113e+05   Fri Feb 17, 2023   07:17:05
   40          2.0919e-08      1.8388e+05   Fri Feb 17, 2023   07:17:48
   41          1.7216e-08      1.7961e+05   Fri Feb 17, 2023   07:18:34
   42          1.9691e-08      1.8318e+05   Fri Feb 17, 2023   07:19:15
   43          1.4191e-08      2.2937e+05   Fri Feb 17, 2023   07:19:57
   44          1.9441e-08      2.1013e+05   Fri Feb 17, 2023   07:20:38
   45          4.6010e-08      2.0278e+05   Fri Feb 17, 2023   07:21:20
   46          6.4672e-08      2.1654e+05   Fri Feb 17, 2023   07:22:01
   47          2.6309e-08      1.9879e+05   Fri Feb 17, 2023   07:22:42
   48          2.5303e-08      1.9170e+05   Fri Feb 17, 2023   07:23:23
   49          1.7855e-08      1.8747e+05   Fri Feb 17, 2023   07:24:04
   50          2.2876e-08      1.8581e+05   Fri Feb 17, 2023   07:24:47
   51          1.7156e-08      2.1835e+05   Fri Feb 17, 2023   07:25:28
   52          1.9992e-08      1.9296e+05   Fri Feb 17, 2023   07:26:10
   53          1.5495e-08      1.8153e+05   Fri Feb 17, 2023   07:26:52
   54          1.7576e-08      1.8018e+05   Fri Feb 17, 2023   07:27:34
   55          2.1264e-08      2.0016e+05   Fri Feb 17, 2023   07:28:16
   56          5.7598e-08      2.1021e+05   Fri Feb 17, 2023   07:28:58
   57          5.1185e-08      2.0055e+05   Fri Feb 17, 2023   07:29:40
   58          2.7393e-08      1.9653e+05   Fri Feb 17, 2023   07:30:24
   59          1.8009e-08      2.2472e+05   Fri Feb 17, 2023   07:31:04
   60          2.1383e-08      1.9777e+05   Fri Feb 17, 2023   07:31:47
   61          1.5448e-08      2.7099e+05   Fri Feb 17, 2023   07:32:28
   62          2.2027e-08      2.1360e+05   Fri Feb 17, 2023   07:33:09
   63          1.8144e-08      1.9227e+05   Fri Feb 17, 2023   07:33:51
   64          2.0051e-08      1.8533e+05   Fri Feb 17, 2023   07:34:33
   65          1.5847e-08      1.8219e+05   Fri Feb 17, 2023   07:35:14
   66          1.7437e-08      1.8076e+05   Fri Feb 17, 2023   07:35:56
   67          1.5126e-08      1.7785e+05   Fri Feb 17, 2023   07:36:37
   68          2.0546e-08      1.7657e+05   Fri Feb 17, 2023   07:37:18
   69          1.6498e-08      1.7678e+05   Fri Feb 17, 2023   07:38:00
   70          1.8724e-08      1.7677e+05   Fri Feb 17, 2023   07:38:41
   71          1.1573e-04      2.1970e+05   Fri Feb 17, 2023   07:39:24
   72          4.8163e-08      2.4947e+05   Fri Feb 17, 2023   07:40:06
   73          2.3002e-08      2.3116e+05   Fri Feb 17, 2023   07:40:47
   74          2.4053e-08      2.1288e+05   Fri Feb 17, 2023   07:41:30
   75          2.0014e-08      1.9955e+05   Fri Feb 17, 2023   07:42:12
   76          1.3195e-06      2.0574e+05   Fri Feb 17, 2023   07:42:53
   77          3.2539e-08      2.0102e+05   Fri Feb 17, 2023   07:43:34
Loosening gap stiffness to improve convergence
   78          2.3099e-07      1.9458e+05   Fri Feb 17, 2023   07:44:15
   79          1.5378e-08      3.8771e+05   Fri Feb 17, 2023   07:44:57
   80          4.6065e-10      3.4422e+05   Fri Feb 17, 2023   07:45:38
Adjusted gap stiffness to prevent interpenetration
   81          1.0244e-05      3.2347e+05   Fri Feb 17, 2023   07:46:19
   82          1.5491e-08      3.1698e+05   Fri Feb 17, 2023   07:47:00
   83          3.6565e-09      2.9462e+05   Fri Feb 17, 2023   07:47:41
   84          6.8412e-06      2.9824e+05   Fri Feb 17, 2023   07:48:24
   85          1.1817e-08      2.9346e+05   Fri Feb 17, 2023   07:49:05
   86          2.5043e-09      2.8267e+05   Fri Feb 17, 2023   07:49:47
   87          6.8605e-06      3.0087e+05   Fri Feb 17, 2023   07:50:28
   88          1.1866e-08      2.9516e+05   Fri Feb 17, 2023   07:51:11
   89          1.0546e-09      2.7080e+05   Fri Feb 17, 2023   07:51:53
   90          3.8126e-10      2.6411e+05   Fri Feb 17, 2023   07:52:35
Adjusted gap stiffness to prevent interpenetration
   91          1.0846e-05      2.8424e+05   Fri Feb 17, 2023   07:53:17
   92          3.3304e-08      3.0010e+05   Fri Feb 17, 2023   07:53:59
   93          2.4314e-08      2.7980e+05   Fri Feb 17, 2023   07:54:43
   94          6.8635e-06      2.8386e+05   Fri Feb 17, 2023   07:55:27
   95          5.9190e-08      2.8131e+05   Fri Feb 17, 2023   07:56:12
   96          9.8588e-08      2.6766e+05   Fri Feb 17, 2023   07:56:54
   97          8.0458e-06      2.8834e+05   Fri Feb 17, 2023   07:57:36
   98          8.1294e-08      2.8023e+05   Fri Feb 17, 2023   07:58:19
   99          5.6426e-08      2.7309e+05   Fri Feb 17, 2023   07:59:00
  100          7.0291e-06      2.8284e+05   Fri Feb 17, 2023   07:59:41
  101          7.1255e-08      2.7621e+05   Fri Feb 17, 2023   08:00:22
  102          8.1001e-08      2.6611e+05   Fri Feb 17, 2023   08:01:07
  103          1.6458e-05      2.8637e+05   Fri Feb 17, 2023   08:01:48
  104          8.8166e-08      2.8570e+05   Fri Feb 17, 2023   08:02:30
  105          4.7127e-08      2.7471e+05   Fri Feb 17, 2023   08:03:11
  106          8.0635e-08      2.6558e+05   Fri Feb 17, 2023   08:03:52
  107          8.3996e-08      2.6504e+05   Fri Feb 17, 2023   08:04:33
  108          1.0161e-07      2.6241e+05   Fri Feb 17, 2023   08:05:16
  109          9.0707e-08      2.8402e+05   Fri Feb 17, 2023   08:05:58
  110          5.8664e-08      2.5479e+05   Fri Feb 17, 2023   08:06:39
  111          6.3605e-08      2.7803e+05   Fri Feb 17, 2023   08:07:19
  112          5.7070e-08      2.6285e+05   Fri Feb 17, 2023   08:08:00
  113          6.7747e-08      2.6181e+05   Fri Feb 17, 2023   08:08:41
  114          9.3685e-08      2.5727e+05   Fri Feb 17, 2023   08:09:23
  115          9.8192e-08      2.5920e+05   Fri Feb 17, 2023   08:10:04
  116          6.1752e-08      2.5765e+05   Fri Feb 17, 2023   08:10:45
  117          4.5283e-08      2.5537e+05   Fri Feb 17, 2023   08:11:27
  118          4.6889e-08      2.5467e+05   Fri Feb 17, 2023   08:12:09
  119          9.4066e-08      2.5475e+05   Fri Feb 17, 2023   08:12:51
  120          1.0892e-07      2.5518e+05   Fri Feb 17, 2023   08:13:33
  121          7.8654e-08      2.5502e+05   Fri Feb 17, 2023   08:14:15
  122          5.5850e-08      2.5414e+05   Fri Feb 17, 2023   08:14:58
  123          6.5924e-08      2.5416e+05   Fri Feb 17, 2023   08:15:40
  124          5.8445e-08      2.5608e+05   Fri Feb 17, 2023   08:16:23
  125          7.4771e-08      2.5475e+05   Fri Feb 17, 2023   08:17:04
  126          9.1982e-08      2.6044e+05   Fri Feb 17, 2023   08:17:46
  127          7.9292e-08      2.5720e+05   Fri Feb 17, 2023   08:18:28
  128          5.7563e-08      2.5723e+05   Fri Feb 17, 2023   08:19:11
  129          5.1478e-08      2.5630e+05   Fri Feb 17, 2023   08:19:52
  130          6.7792e-08      2.5582e+05   Fri Feb 17, 2023   08:20:35
  131          6.7552e-08      2.5458e+05   Fri Feb 17, 2023   08:21:19
  132          1.3451e-05      2.7547e+05   Fri Feb 17, 2023   08:22:01
  133          9.9186e-08      3.0008e+05   Fri Feb 17, 2023   08:22:43
  134          6.1487e-08      2.8062e+05   Fri Feb 17, 2023   08:23:26
  135          9.8840e-08      2.6977e+05   Fri Feb 17, 2023   08:24:08
  136          7.1119e-08      2.6732e+05   Fri Feb 17, 2023   08:24:50
  137          8.4347e-08      2.6239e+05   Fri Feb 17, 2023   08:25:34
  138          8.4888e-08      2.8356e+05   Fri Feb 17, 2023   08:26:16
  139          8.8095e-08      2.7001e+05   Fri Feb 17, 2023   08:26:58
  140          5.7661e-08      2.6567e+05   Fri Feb 17, 2023   08:27:40
  141          5.2874e-08      2.6346e+05   Fri Feb 17, 2023   08:28:22
Loosening gap stiffness to improve convergence
  142          2.4066e-07      2.5976e+05   Fri Feb 17, 2023   08:29:04
  143          1.8710e-08      4.2414e+05   Fri Feb 17, 2023   08:29:46
  144          1.4229e-11      3.7598e+05   Fri Feb 17, 2023   08:30:28
Adjusted gap stiffness to prevent interpenetration
  145          2.8200e-08      3.5965e+05   Fri Feb 17, 2023   08:31:12
  146          1.8107e-09      3.2997e+05   Fri Feb 17, 2023   08:31:55
  147          1.4521e-06      3.1972e+05   Fri Feb 17, 2023   08:32:37
  148          8.4482e-09      3.4040e+05   Fri Feb 17, 2023   08:33:19
  149          7.1332e-07      3.3546e+05   Fri Feb 17, 2023   08:34:01
  150          6.1081e-09      3.3426e+05   Fri Feb 17, 2023   08:34:48
  151          7.0771e-07      3.3504e+05   Fri Feb 17, 2023   08:35:31
  152          6.1759e-09      3.3538e+05   Fri Feb 17, 2023   08:36:14
  153          1.4985e-06      3.2793e+05   Fri Feb 17, 2023   08:36:57
  154          8.2031e-09      3.4151e+05   Fri Feb 17, 2023   08:37:40
  155          7.2095e-07      3.3592e+05   Fri Feb 17, 2023   08:38:23
  156          6.9027e-09      3.3350e+05   Fri Feb 17, 2023   08:39:03
  157          7.0358e-07      3.3479e+05   Fri Feb 17, 2023   08:39:46
  158          7.2600e-09      3.3489e+05   Fri Feb 17, 2023   08:40:29
  159          1.4456e-06      3.2722e+05   Fri Feb 17, 2023   08:41:11
  160          8.4897e-09      3.4237e+05   Fri Feb 17, 2023   08:41:55
  161          7.1577e-07      3.3672e+05   Fri Feb 17, 2023   08:42:37
  162          6.8557e-09      3.3388e+05   Fri Feb 17, 2023   08:43:20
  163          7.0876e-07      3.3475e+05   Fri Feb 17, 2023   08:44:03
  164          6.8628e-09      3.3492e+05   Fri Feb 17, 2023   08:44:45
  165          1.5032e-06      3.2760e+05   Fri Feb 17, 2023   08:45:29
  166          8.6942e-09      3.4225e+05   Fri Feb 17, 2023   08:46:14
  167          7.2145e-07      3.3608e+05   Fri Feb 17, 2023   08:46:59
Loosening gap stiffness to improve convergence
  168          4.9275e-08      3.3360e+05   Fri Feb 17, 2023   08:47:43
  169          7.1184e-08      4.3826e+05   Fri Feb 17, 2023   08:48:27
  170          9.7485e-10      4.1120e+05   Fri Feb 17, 2023   08:49:11
Adjusted gap stiffness to prevent interpenetration
  171          1.6248e-07      4.0265e+05   Fri Feb 17, 2023   08:49:56
  172          1.7094e-09      3.8165e+05   Fri Feb 17, 2023   08:50:40
  173          7.2348e-08      3.7901e+05   Fri Feb 17, 2023   08:51:24
  174          1.1007e-09      3.7317e+05   Fri Feb 17, 2023   08:52:06
  175          1.5279e-07      3.7274e+05   Fri Feb 17, 2023   08:52:48
  176          1.6686e-09      3.7340e+05   Fri Feb 17, 2023   08:53:32
  177          7.2210e-08      3.7132e+05   Fri Feb 17, 2023   08:54:16
  178          1.0986e-09      3.6944e+05   Fri Feb 17, 2023   08:55:01
  179          1.5281e-07      3.7019e+05   Fri Feb 17, 2023   08:55:45
  180          1.6672e-09      3.7186e+05   Fri Feb 17, 2023   08:56:29
  181          7.2214e-08      3.7710e+05   Fri Feb 17, 2023   08:57:14
  182          1.0986e-09      3.7342e+05   Fri Feb 17, 2023   08:57:59
  183          1.5281e-07      3.7270e+05   Fri Feb 17, 2023   08:58:45
  184          1.6673e-09      3.7354e+05   Fri Feb 17, 2023   08:59:30
  185          7.2205e-08      3.7138e+05   Fri Feb 17, 2023   09:00:14
  186          1.0987e-09      3.6952e+05   Fri Feb 17, 2023   09:00:59
  187          1.5281e-07      3.7012e+05   Fri Feb 17, 2023   09:01:45
  188          1.6670e-09      3.7182e+05   Fri Feb 17, 2023   09:02:27
  189          7.2211e-08      3.7710e+05   Fri Feb 17, 2023   09:03:10
  190          1.0986e-09      3.7343e+05   Fri Feb 17, 2023   09:03:52
  191          1.5281e-07      3.7269e+05   Fri Feb 17, 2023   09:04:35
  192          1.6673e-09      3.7355e+05   Fri Feb 17, 2023   09:05:16
  193          7.2205e-08      3.7141e+05   Fri Feb 17, 2023   09:05:58
Loosening gap stiffness to improve convergence
  194          1.3992e-08      3.6951e+05   Fri Feb 17, 2023   09:06:39
  195          1.5492e-08      4.8051e+05   Fri Feb 17, 2023   09:07:21
  196          3.0527e-10      4.6902e+05   Fri Feb 17, 2023   09:08:08

[EddyVE]

Can you post a few screenshots of your assembly? That would help us in understanding what you are trying to do.

[ilyachaban]

sorry can't post screenshots here is a sketch of a half of it and some connections

Bolted connection

pin connection

rough sketch

[skunks]

contacts are very complicated, please upload STEP

[ilyachaban]

Sorry wrong formulation. I can't post work that i'm doing

[skunks]

OK, I am going to build a simple example

[skunks · Accepted solution]

example contact

[ilyachaban]

Simulation that has that many elements actually works. There is no problem for me to simulate 2 parts in contact but when there is more parts simulation doesn't converge at all. 

[skunks]

in the model there are contact gaps, depending on the absolute accuracy

[ilyachaban]

What do you mean by contact gaps

Is that it?

If it is: how did you choose 0.015?

[skunks]

yes: contact gap 0.15 mm > absolute accuracy 0.1 mm

[skunks]

sorry: contact gap 0.015 mm > absolute accuracy 0.01 mm

[ilyachaban]

Is there any literature that defines that or it is your expirience with PTC Creo Simulate?

[skunks]

literature in german ...

[ilyachaban]

Because I've seen in literature that creo converge easily if you turn on friction and create interpenetration. so cylindrical connection has some friction under the head and has something to prevent it from rotation.

[skunks]

turn on friction is completely wrong way

[SweetPeasHub]

Many contacts in Creo is difficult.

One tip I have is for a pin, to add a low stiffness spring (red color) to add some constraint to an otherwise loose pin.

[skunks]

I developed something like this about 12-13 years ago

[ilyachaban]

Hi, thank you for your tips about contact gaps and friction. For now I have working model that converges very quickly. I didn't see your tip about axial rotation tip but i will use it 100%.

What degrees of freedom does this spring limits all 3 or only in tangential direction? 

[skunks]

thanks,

for example

[skunks]

only necessary degrees of freedom, so that no rigid body displacement and no rigid body rotation take place

[ilyachaban]

Thank you

[ilyachaban]

Thank you. Will try this one too. Now with the help of @skunks my model is working.

[PP_10622270]

Hello,

I came here to say only  that solution worked for me thanks to the community and the members for the solution. please keep sharing such post here .

[olivierlp]

Thank you for the appreciation, @PP_10622270, and welcome to the PTC Community!

Thanks also to all participants in this topic!