Hi, I have a complicated ductwork assembly with many doors, gaskets, panels, etc. I want to run a flow simulation study with an inlet volume flow rate and and outlet pressure, but it is difficult to seal off the internal volume and allow the study to be run as and internal flow. Flow in and out of ductwork seems like a classic internal flow problem, but is there any disadvantage to simply running it as an external study and letting it leak a bit? the only thing I can think of is a few extra cells in the mesh. i know the computational domain looks different in internal vs external simulations, but does solidworks actually do anything differently when it runs the simulation? Thanks!
Theoretically you should get almost the same results. I would watch out for tiny gaps and cracks which may cause a concentration of cells or could spike your RANS errors and destabilize the simulation. No harm in trying it at least.