[geraldnjw]

Hello all, I am simulating the pressure wave in a room resulting from a heat source.

I want to create a geometry of a box within a box with a hole that allows gas to escape from the smaller box (where the heat source is in).

I first made the large box using blockMesh and made the small box with internal faces using topoSet and createBaffles. What left me confused was when I had to create a patch for the "hole" since it has to both function as an inlet and outlet. Should it also be created using topoSet and createBaffles? If so, how would it be known which faces are the "inlet" and "outlet" for the fluid?

I've also attached a picture showing the big box and small box that I've managed to make so far. Thanks!