How to make matched surface msh for periodic boundary in CFD

Hi all,

I am new in Trelis and want to generate mesh with Trelis for CFD simulation. Currently I am working with one simplified geometry and would like to run the demo with periodic conditions. However, I am quite confused [b]how to generate the matched surface mesh on surface pairs which would set periodic conditions subsequently.[/b] Could you please do me a favor about it?  Thank you so much for your support.

Thomas