one fin instead of an array of fins
 

hi,
im trying to simulate a row of tubes,
i want to use one fin instead of all of them,by simulating one fin and defining aximmetric boundary for right and left,
but i don't know how to do this, i searched a lot but it didn't help, anyone can help me?
here is a top view schematic:

You should define translational periodic boundaries on the left and right faces, and impose a flow rate or pressure drop across them to drive the flow.

thank you, flow in this case is from up to down, not left to right, how do i find flow rate or pressure drop for those?
i taught we define a bc that counts the effect of adjacent fins and we don't need to define any parameter.

The usual approach is to use periodic boundary pairs. They are the same as I mentioned in my previous post, except you don't impose a pressure difference or flow rate across it.

You can use symmetry boundaries, but only if the flow is truly symmetric.

thanks, it's very useful.