concept of periodic conditions
 

How can we use same periodic conditions to
1.flow with a pressure drop,which is geometrically periodic in nature,and is not fully developed.
and also to
2.Flow with a pressure drop,and fully developed flow(like fully developed flow through circular pipe)
Iam getting confused.

case 2 is for example the flow driven by a pressure gradient in a channel. You can decompose your pressure in two terms, one is the mean constant pressure gradient you use as forcing in the momentum equation, the second is the "fluctuation" that you set periodic. This last term is governed by the Poisson equation for incompressible flows

concept of periodic conditions
 

Thanks for the response.
Can you please explain me how can be the same periodic conditions procedure be applied such that we find du/dx=0 in second case and du/dx not equal to zero in first case.

pressure drop in periodic flow
 

Hi
I have simulated flow over solids through a channel.I have applied periodic boundary conditions at the inlet and exit of the pipe. Can I use the pressure drop indicated in periodic boundary conditions menu after the convergence of the case as pressure drop /L for my further work?
Any one please clarify.