Can we set min time increment less than 1e-5

General Questions
1

can we set min time increment less than 1e-5? when i set it ,it seems that it does not take efffect.
min time increment

state
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2

Minimum time increment means the lowest increment size that CalculiX will be allowed to use during the analysis if necessary. In this case apparently there was no need for the solver to drop that low with increment size.

3

I was also testing this setting a while ago and found out that it cannot be set lower than 1e-5 of the time period. I changed the time period to a higher value since I thought that 1e-5 is the lower absolute limit for the time step but it turned out that increasing the time period also increases the lowest possible time step. I searched the documentation about this but I did not find any clues. I know that in Abaqus it is possible to use values lover than 1e-5. Does anybody know about this limitation?

4

Some time ago I asked about this on the CalculiX forum: Minimum time increment can't be lower than 1e-5 - CalculiX

Then I sent an e-mail to Guido about this and other issues and today I got the reply. He solved all these nasty bugs and replied to their corresponding threads on the forum. As you can see, it turns out that for static steps there’s a hardcoded limit of 1e-6 for increment size (but in some cases it was 1e-5 and this was fixed) since lower increments rarely lead to a converged solution. I’m not sure about this and I will ask Guido to at least mention this in the documentation but maybe I will also convince him to remove the increment size limit.

1 Like
5

Thank you for contacting Guido and trying to solve this issue.

I also think that this would be the best solution.