{"id":369338,"date":"2024-05-31T07:37:29","date_gmt":"2024-05-31T07:37:29","guid":{"rendered":"\/forum\/forums\/topic\/best-option-for-ls-dyna-restart-in-workbench\/"},"modified":"2024-05-31T08:37:23","modified_gmt":"2024-05-31T08:37:23","slug":"best-option-for-ls-dyna-restart-in-workbench","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/best-option-for-ls-dyna-restart-in-workbench\/","title":{"rendered":"Best Option for Ls-Dyna Restart in Workbench"},"content":{"rendered":"

Hello community,<\/p>\n

this is my first time trying to set up a Ls-Dyna Restart simulation. I tried different methods but each seem to come with their own difficulties.
I would greatly appreciate solution approaches.<\/p>\n

First Option: Export dynain file and import via external model into new Ls-Dyna system<\/strong>
Advantages: Import deformed mesh and initial stresses.
Issues: Weird artifacts – perhaps due to initial penetration of contacts.
I tried to check for and handle this with a keyword snippet:
*CONTROL_CONTACT
$#  slsfac    rwpnal   islchk   shlthk   penopt   thkchg   orien    enmass
      0.0       0.0       0        1        1        0        2        0
$#  usrstr
      0
$#  sfric
      0.0
$#  ignore    frceng   skiprwg  outseg   spotstp  spotdel  spothin
      0         1        0        1        0        1        0.5
*END
\"\"<\/a>
Second Option: Ls-Dyna Restart systems in Workbench
<\/strong>Advantages: Easy to understand
Disadvantages: Limited features-especially full restart
I started with a small restart to delete parts that are not needed for the restart(the full restart does not seem to support that). I tried keyword snippets to delete those parts in the full restart but even though no error appeard the parts continued to exist.
With the small restart before the full restart, I can delete those parts. However the full restart only works when connected to the original Ls-Dyna system and not when connected to the small restart.<\/p>\n

<\/a><\/p>\n

First Option: Export dynain file and import via external model into static structural
<\/strong>Advantages: No weird artifacts
<\/strong>Issues: The initial stress state is imported but based on the stresses at time 0, the stresses are not applied.<\/p>\n

best regards,<\/p>\n

Marco<\/p>\n","protected":false},"template":"","class_list":["post-369338","topic","type-topic","status-closed","hentry","topic-tag-ansys-ls-dyna-1","topic-tag-apdl-command","topic-tag-contact","topic-tag-lsdyna","topic-tag-penetration","topic-tag-restart","topic-tag-restart-analysis-1","topic-tag-static-structural","topic-tag-workbench"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t