PERIODIC BCs in staggered framework

[BSFEAP]

Dear All,
For imposing periodic boundary conditions for thermal problem in FEAP, one can use

PERI, THER
0 0 1
0 0 0
0 0 0

CBOU  (for one point)
node, -20, -20, -20, 1
node,  20, -20, -20, 1
node, -20,  20, -20, 1
node,  20,  20, -20, 1
node, -20, -20,  20, 1
node,  20, -20,  20, 1
node, -20,  20,  20, 1
node,  20,  20,  20, 1

END         
tie

ELINK
3, 20, -20, 0, 0
2, 20, -20, 0, 0
1, 20, -20, 0, 0

Now I am solving two thermal problem in staggered manner by using Partition.
Could we also impose periodic BCs for both thermal fields? Thanks a lot.

[Prof. R.L. Taylor]

Probably not.  The periodic conditions are not looking at partitions to see which boundary conditions are being used.  Furthermore the input of the PERI does not have a way to associate the specified gradient to a particular partition.

You will need to program user modules to do what you want to describe.

[BSFEAP]

Thanks a lot Prof. Taylor for your answer. Could you please give any hint to program this? For instance, based no which file from FEAP, we can program it.

[Prof. R.L. Taylor]

The input for PERI is stored in ./program/periodic.f

After you solve the problem the homogenization is done in ./program/phillmandel.f

Thus you need to follow how the data is used and modify for each partition accordingly.

It is not clear what the relationship between the two thermal problems is.  Do they interact?