Keyur Kanade
Ansys Employee

I assume you have A.msh and B.msh for fluid regions. In Fluent you can append mesh files and create non conformal mesh. 

If you want to have conformal mesh then you will need to use ICEMCFD to connect A and B. The recommended approach is form a single part in DM and use share topo and then mesh it to have conformal mesh. 



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