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How to change the value of time increment every step in vumat?

Hello, all


I have a new question in using vumat. As you know, time increment, dt,  is usually  determined in the xxx.inp before calculation. I know there are two ways, automatic or constant.

I want to know if there is the third way. So, I can control the value of dt for every step according one state variable I defined. 

This idea seems a little crazy. But this is really very important for my code.

Please give me some help.





At first it seemed like the question was going to be easy, as I know you can update dtime in UMAT, but when I looked up the documentation for VUMAT, I saw that you could not update dt. That being said, in your shoes I'd try just to make absolutely sure that the manual does not improperly document it. If it is indeed the case that there is nothing you can do inside VUMAT to update the time increment, you might have to combine your VUMAT with a complementary script outside the simulation to change the time increment for the simulation, but this is a lot of computing overhead and a lot more work; it hardly seems like a good solution.

Hopefully someone else can be more helpful than I.




Hi, Mike


Your solution seems too hard for me.  Thank you for your reply.





Hi Wang,

as far as I know you can't modify the value of dt within your vumat-subroutine.



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