First, you perform a generation pass for your sub-super elements. Then you perform another generation pass for an assembly of your sub-superelements (MATRIX50) with master-degree-of-freedom for the assembly superelement. In the use pass, you assemble these superelements(which contains sub-superelements). And then perform the expansion pass for the superelements in which contains the displacements for the sub-superelements only. Then you perform another expansion pass for the sub-superelements to obtain the stresses. The requirement is that both superelement and sub-superelements contains linear elements only.
Hai Ly
To: 'xansys@o...'
Hi Hae Ly,
I tryed to avoid substructuring till now but the size of the problem I am solving right now is forcing me to go and learn it. I like the idea of nested substructuring very much. Can you elaborate on the potential road blocks if you do something like this?
-----Original Message----- Sent: Friday, December 18, 1998 10:05 AM To: xansys@o...
Marc,
Another way you can reduce numbers of substructures by using nested substructuring - you have 8 super-element each have 4 sub-superelement itself. This way reduces both numbers superelement as well as numbers of master degree of freedom. There is more than one way to skin the cat.
Hai Ly AlliedSignal Equipements & System
>From: Marc Seidel >To: xansys@o... >Subject: [xansys] Substructuring >Date: Friday, December 18, 1998 1:35AM
>From: Marc Seidel
>Thanks to everybody who helped me to get started with substructuring so far! >But I have a new problem: My model is very large, I have to import my >substructure 32 times. Even though the number of master nodes is small (for >one substructure about 100 nodes) the node numbers are in a wider range >because of gaps between the master node numbers. So if I import my >substructures I have to increase the node numbers by a large offset value >(using SETRAN) so that the node numbers exceed 64000 in my main model.
>Is there a way to renumber the nodes so that the master nodes are the first >nodes from node number 1 to 100, numbered consecutively? I could use a >smaller offset value then so that highest node does not exceed 64000.