Pipe Flow Expert is not able to model two phase flow, such as gas/liquid mixtures. 

When two different fluids are mixed together it is possible that two-phase flow may occur at some point in a system. Pipe Flow Expert does not calculate the pressure drop for two-phase flow.


Two-phase flow can produce an extremely high pressure drop many times greater than the pressure drop of either individual fluid. The user should make due allowance for the two-phase flow pressure drop by using a component to add an appropriate additional pressure loss.