PERIODIC BOUNDARY CONDITION
 

I would like to study a fully developed flow in a section module of a heat changer. I've seen that it's impossible to set up the inlet and outlet as "mass flow rate" and "periodic" at the same time. Fixing an initial value of the velocity in all the domain causes a diminishing of the velocity during the iterations.

Someone can help me?

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| | | in | | out --->| _______ | ----> _ _ _ _ |

| | | | _ _ _|______| |______|_ _ _ _| | _ _ _|