is it possible to change material properties during restart? 1

[roudan]

Hi

I have many time steps and doing history matching. After the first run, I'd like to change material properties such as Young's Modulus during restart. I am thinking to use user subroutine or field variable to define Young's modulus as function of field variable or statev(). I am wondering if it is possible to change this relationship( E vs. a variable) in user subroutine during restart? And which user subroutine is the best to do this job? Thanks

 

[FEA way]

Normally material properties can't be changed when using restart but there are other ways. You could use import analysis for that. Another option is described here:

https://www.eng-tips.com/viewthread.cfm?qid=259881

But it can be done without editing keywords manually.

 

[roudan]

Thank you FEA Way, I am actually using the 2nd option of using field variable and change field variable for different steps. The problem is that the material properties as function of field variable is already input the initial run and then I cannot change it during restart. Am I correct? That is why today I am wondering if I could use user subroutine? Now another question is: can I change user subroutine during restart? Thanks

 

[FEA way]

You can define initial value of field variable and then change it in selected step using predefined field.

When it comes to subroutines, USDFLD may be helpful in this case. Subroutines can be modified on restart.

 

[roudan]

Thank you so much FEA Way