Defining solution parameters

Hello,

I saw in a few posts, that from v2021R2 on it is possible to define own parameters.

I want to define three Stress Intensity Factors along the crack as an output parameter.
At point 1, 16 and 31 of my crack front division. Is that possible and how?

Thank you so much.

Best regards,

Viktoria

Find more posts tagged with

Accepted answers

Mike.Thompson

You can do this with an APDL command snippet under the solution. This is an example of how to select a node by its index along the crack front (ARG1). The output of this will be 'my_K1' and will be parametric as needed in mechanical/workbench

!------------------------- Notes -------------------------
!This will calculate the fracture paramters for a crack via *GET CINT operations
!It will allow to have the calculated values set as parametric if desired by using the Output Search Prefix option
!------------------------- User Args -------------------------
!If using this by: "RMB>Execute Post Commands" you need to explicitly change the MyCrackId as it wont be known from the previous model
!MyCrackId = 1 !- > defined in the command object under the Crack in Fracture branch

CrackNodeIndex = ARG1 !Index of the node along the crack front. NOT the node ID
ContourNum = ARG2 !Contour number to use for the evaluation

!------------------------- General routine -------------------------
/POST1
SET,LAST

!export all the CINT info to a file: Fracture.out
/OUTPUT,'Fracture.out'
PRCINT, MyCrackId, ALL, K1
/OUTPUT

!get the node Id of the node at the index = CrackNodeIndex
*GET,nId,CINT,MyCrackId,NODE,CrackNodeIndex
!Get the SIF_I from the requested data
*GET,my_K1,CINT,MyCrackId,CTIP,nId,CONTOUR,ContourNum,DTYPE,K1
!------------------------- END -------------------------

All comments

Mike.Thompson

CrackNodeIndex = ARG1 !Index of the node along the crack front. NOT the node ID
ContourNum = ARG2 !Contour number to use for the evaluation

!------------------------- General routine -------------------------
/POST1
SET,LAST

!export all the CINT info to a file: Fracture.out
/OUTPUT,'Fracture.out'
PRCINT, MyCrackId, ALL, K1
/OUTPUT

Viktoria33

Perfect, thank you so much, that already helped a lot. Now there is a text file with all the SIFS at the output of each design point. That already is really good.

Unfortunatly it says 0 is there a mistake I made?
I think it is the Index of the node along the crack, which one is that exactly/how do I find that out?