Ansys Learning Forum › Forums › Discuss Simulation › Fluids › Volume Fraction too Low. How to Improve? › Reply To: Volume Fraction too Low. How to Improve?
Re-read the inlet pressure option you've picked as it's not going to do anything in this scenario. The inlet pressure is whatever is required to push the vapour mass into the domain against the outlet pressure.Â
For this I'd tend to set the "outside" tube wall (wet tube side boundary) as you have above but with an HTC and temperature that's appropriate to the system - there are correlations for horizontal & vertical tubes in the literature. If you can't find a value go and ask a Chemical Engineer nicely as it's in most of the first year text books. Retain the "coupled" setting on the wall-wall:shadow pair otherwise there's no heat transfer. Â