Periodic boundary condition (periodic BC) is very useful and time saving feature when you working with repeating geometries. With Periodic BC, you will have less number of mesh elements, so faster simulation to get results. In this example, we have 25mm diameter, 50mm long smooth pipe and we will see how to avoid errors while setting up periodic boundary conditions. Let's start with Fluent Meshing, then I will show how to match periodic faces in classical meshing window. Afte