Defining the Phase Interactions

Define the interactions between the liquid and vapor phases. The liquid phase is boiling and the vapor phase is the product of boiling.

When you create a phase interaction, you select the primary phase first, and then the secondary phase. In this simulation, the primary phase is H2O and the secondary phase is H2O (G).

To define the phase interactions:

  1. In the Boiler continuum, right-click the Models > Multiphase Interaction > Phase Interactions node and select New > H2O > H2O (G).
  2. For the Phase Interaction 1 phase interaction, select the following models in order:

    Group Box

    Model

    Optional Models

    VOF Boiling

    Boiling Models

    Rohsenow Boiling

    Multiphase Material (selected automatically)

  3. Click Close.

Wall heat flux due to boiling is a highly non-linear function at wall boundaries where the wall temperature is part of the numerical solution. For example, for given heat flux wall boundaries or solid-fluid interfaces. In these cases, to improve the convergence, you can reduce the under-relaxation factor for heat flux due to boiling (Under-Relaxation Factor property under the Rohsenow Boiling node).



  1. Save the simulation.