Fluid Film Phase Interactions

You specify the Fluid Film phase interaction model to control the interaction between the fluid film phase and another phase.

When the Fluid Film model is activated in the physics continuum, the phase interaction models that are appropriate for the physics continuum become available.

  • DMP-Film Interaction

    Controls the interaction between the fluid film and a dispersed phase, such as fluid droplets impinging on a surface film. This model is available for Dispersed Multiphase (DMP) simulations only.

    The dispersed phase interacts with the fluid film phase by impingement of droplets from the dispersed phase into the fluid film and stripping of droplets from the fluid film into the dispersed phase. Only single-component fluid film is supported, as DMP uses a single-component dispersed phase.

    The Dispersed Multiphase model can be used as a lightweight replacement for Lagrangian particles in simulations where the LMP model is too computationally expensive due to the large number of particles. Wave and edge stripping transfers droplets from the fluid film phase into the dispersed phase of a DMP simulation. Using DMP particles for icing and soiling simulations is significantly quicker than using Lagrangian particles.

  • Film-EMP Phase Interaction

    Controls the interaction of the fluid film with a specified Eulerian phase, such as fluid droplets impinging on a surface film. This model applies to Eulerian Multiphase (EMP) simulations only.

    Mass can be transferred by impingement from a dispersed Eulerian phase into the fluid film domain, and film stripping can transfer fluid film mass to the dispersed Eulerian phase. For impingement, both single-component and multi-component phases are supported. However, for wave and edge stripping, only single-component fluid film and Eulerian phases are supported. This model is used when the physics continuum contains multiple phases (typically a continuous phase and one or more dispersed phases), and allows you to specify the particular Eulerian phase with which the fluid film interacts.

  • Film-Lagrangian Phase Interaction

    Controls the interaction between the fluid film and a Lagrangian phase, and is used for modeling droplet impingement or film stripping in a Lagrangian Multiphase simulation. This model is available for Lagrangian Multiphase simulations only.

  • Film-MMP Phase Interaction

    Controls the interaction of the fluid film with a specified Eulerian phase, such as fluid droplets impinging on a surface film. This model applies to Mixture Multiphase (MMP) simulations only.

    Mass can be transferred by impingement from a dispersed MMP phase into the fluid film domain, and film stripping can transfer fluid film mass to the dispersed MMP phase. Both single-component and multi-component phases are supported.

  • Film-Physics Continuum Interaction

    Controls the interaction between the fluid film and a single background phase, such as a gas condensing onto or evaporating from a surface, or fluid film boiling when the temperature of the heater surface exceeds the liquid boiling point.

    Both single-component and multi-component Fluid Film phases are supported. This model is available in most multiphase simulations. The exceptions are Eulerian Multiphase (EMP), in which you use the Film-EMP Phase Interaction model instead, and Mixture Multiphase (MMP), in which you use the Film-MMP Phase Interaction model instead.

  • Film-VOF Phase Interaction

    Controls the interaction between the fluid film phase and a VOF phase. This model automatically uses the phase model (fluid film or VOF) that is most suitable for the local flow regime and the computer resources that are available. This model is available for Volume of Fluid (VOF) simulations only.

    This phase interaction is not supported for Steady simulations.

    The primary application of this phase interaction model is in simulations when a fluid film can accumulate in particular areas of the geometry to form pools. In those areas, the accumulated fluid is modeled as a VOF phase rather than as a thin fluid film.

    Both single-component and multi-component fluid film phases are supported. For a multi-component material, you map the component pairs between the phases. Note that only a complete mixture mapping is supported.

    See Resolved Fluid Film Model Reference.