Hi researchers
In UAMP there are props variables like UMAT subroutine but i don't know how to specify constants in abaqus cae like UMAT. in UMAT you specify props in property module but where should i specify props for UAMP in abaqus?
Thanks
I am not sure I understand what you are saying, could you describe what it is you want to do with the UAMP subroutine?
This subroutine is used to define amplitudes, generally changing depending on sensors information. The only properties you can define for this subroutine in the CAE environment is the number of solution dependent variables it can use (and the name of the amplitude).
What are those "props" (properties?) you wan to define? If they are material properties which change depending on temperature/strain/etc., you can use an UMAT subroutine block to define these properties and then pass them as global parameters.
If they're just constants, you can define their values at the beginning of your UAMP block.
Hi Etienne and thank you for your answer
props are variables in UAMP like UMAT. in UMAT you enter props in the property module when you specify user material behavior. my question is how to enter props for UAMP like UMAT? i entered props for UAMP in property module but UAMP didn't use them is there any other place in Abaqus cae for entering props for UAMP?
I am using UAMP for defining time dependent pressure and i want to enter step time and some other constants in UAMP from Abaqus cae like entering constants for UMAT in property module but when you define UAMP you can just enter number of SDVs and you can't enter constants like UMAT.
Hi Mhdi,
Yes like I said, you can only define the number of Solution Dependent Variables (SDVs) through the CAE environment. For the rest, you have to write it in the subroutine code itself.
Note that according to ABAQUS documentation on the UAMP subroutine (which can be found for ABAQUS v6.11 with a quick google search), current value of step and total time are passed as information to the subroutine by the program.
If you need to use the time length of your step in your subroutine, you can specify it as a parameter by adding a parameter line at the beginning of your subroutine.
For example, if the time length of your step is 1500s, just type PARAMETER(tStep=1500D0), just like in the example given at the end of the documentation on UAMP subroutine.
You can define as many parameters as you wish using this line of code (see example in documentation again).
Of course, with this method, you would have to modify the value you entered as a parameter every time you modify the time length of your step, but unless you plan on automatizing calculations with changing step time length with each calculation, that shouldn't be too hard to do.
Ok i found the problem
Props and nprops variable that i talk about them have been added in Abaqus 6.12 and these variables doesn't exist in the previous versions of abaqus like abaqus 6.11. these variables are the same ones that exist in UMAT but i don't know how to enter constants in abaqus like i do for UMAT. you can see Abaqus 6.12 documentation for UAMP subroutine to see the difference with the previous versions of Abaqus.
Thanks so much for your help and attentions Etienne
Hi friends
I got my answer
Because props variables are added in Abaqus 6.12 I read Aabaqus release notes” and understood that I must define values for props in inp file and it is not possible to enter props values in in abaqus cae for now. This is not a new thing and there are some other capabilities in abaqus that you can only use them in inp file and through keywords in abaqus.
Thanks so much Etienne
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