Rob
Ansys Employee
If you're expecting multiphase flow regime change then breaking the domain up adds it's own problems. Namely getting the pressure right as the gas expands. This is why the papers are using HPC and modelling the whole length. Divergence isn't a feature of the domain, but more likely a result of the mesh and/or time step. nWhat are you wanting to see in the CFD model and can you reduce the length by using some calculations with a Baker Chart? n