I have built a RVE in Ansys and I know the equation of periodic boundary condition. However, I'm struggling in applying the equation in Ansys. I have read some thesis that they are using constraint equation or APDL. Which method should I use?
To implement periodic boundary condition in Ansys, you have the following two options:
1) You might couple the dofs of the corresponding nodes in the corresponding directions. You might give a look at coupling through offset nodes. Have a try with CPCYC along with a rectangular cartesian co-ordinate system to have the desired result. I prefer this one as it seems simple to me.
2) You might also give a try to using constraint equation to define some specific relation between the corresponding nodes of the boundary.
Please have a look at the attached document for further clarification.
You have to write an equation between the two opposite nodes in your RVE. Take care about the common nodes on edges and corners of the RVE( they have to be defined once).
For example:
U1 (@node1)-U1(@node2)-delta=0
Do the same for U2, and U3 DOF's.
Delta is the applied displacement. If your delta is zero, you will have: