middle nodes for optimization

[seseb]

Hello

I'm doing a geometrical optimization and I try to minimize the VM stress. It works but I could notice that when I want to get the maximum value of VM stress (from "PRNSOL,S,PRIN") I get only results from the external nodes of my elements (not middle node). I use Solid95 (10 nodes, tetraedral) element.
So now I have some questions
1° Is it possible to get result nodal list from all nodes (middle and external nodes)?
2° If we can get the result on all nodes, is it necessary for an optimisation to minimize on all nodes or external nodes of each element are enough?
3° Why when I use "/GRAPHICS,FULL" instead "/GRAPHICS,POWER", my results on display changes (especially if I have few bad shape elements) but I still get only external nodes with "PRNSOL,S,PRIN"?

Best Regards
seseb

 

[qwicker]

Well first of all, solid 95 is a 20-node brick. Did you mean Solid 92?

If you want to list your nodal solution, you can accomplish that via the list command, nodal solution.

I have a question though, what do you mean you are performing a geometrical optimization to minimize stress? Is that an ansys feature or are you building models, solving them, then building another model, etc?

 

[seseb]

Hello,

Sorry I did a mistake, it was SOLID92 (SOLID95 with tetrahedral option).

So I know that I can get the nodal solution via the list command, nodal solution but if you do that, you don't get the results from all nodes.

I give you a really simple exemple:
/PREP7
ET,1,SOLID92
MPTEMP,,,,,,,,
MPTEMP,1,0
MPDATA,EX,1,,2.1E11
MPDATA,PRXY,1,,0.3
BLOCK,0,2,0,2,0,20,
MSHAPE,1,3D
MSHKEY,0
CM,_Y,VOLU
VSEL, , , , 1
CM,_Y1,VOLU
CHKMSH,'VOLU'
CMSEL,S,_Y
VMESH,_Y1
FINISH
/SOL
FLST,2,1,5,ORDE,1
FITEM,2,2
/GO
DA,P51X,ALL,0
FLST,2,1,5,ORDE,1
FITEM,2,1
/GO
SFA,P51X,1,PRES,-100
/STATUS,SOLU
SOLVE
FINISH
/POST1
PRNSOL,S,PRIN

So from this, you can see that on the list you only get the node number: 1,2,4,6,8 and so on. And then you can notice that nodes 3,5,7, and so on are middle nodes on the elements.
So now, how is it possible to get the result on these middle nodes

About the geometrical optimization. I made a code wich use /OPT with some design variables and the goal is to minimize the VM stress

Best regards
seseb

 

[seseb]

Hello

So, no one has any proposition?

Best regards
seseb