Flow modeling in 2D geometry as helical coil
 

Hello,

I'm trying to setup helical coil heat exchanger using 2D geometry. Now if one takes cross-section of 3D helical coil, then the person should see bunch of circles aligned next to each other in form of array. Sure, its not possible to setup helical flow in this 2D section because all 3 dimensions play critical role. The flow moves X,Y,Z directions.

Now, correct me if I'm wrong but if I put the periodic boundary conditions for each of these circles and periodicity setup only for velocity variable, will it work?
The attached geometry shall provide 'some-what' idea that I'm talking about, in that the arrows that are pointing from one circle to another circle is essentially a flow pathway that I'm trying to achieve with periodicBC on each circle.