Conditions

This section discusses the settings for the Multiphase module.

Click Multiphase in the Model Panel. The following conditions and parameters are available in the Properties Panel:

Components: Allows for the addition (or deletion) of any number of immiscible fluids (e.g. oil, water and air). The components will be named comp_1, comp_2, etc. The components can be renamed by double clicking on the tab containing their respective names. The fluid properties of the components are specified in the appropriate modules (e.g. Flow, Heat, and Common).
Anti-diffusion: Anti diffusion is used to control the phase diffusion.
Numerics: Parameters and schemes used to solve the equations.
VOF Interaction: The level of interaction between the phases can be specified. Specify the VOF Interaction as mild or strong, if the interaction between the phases is weak or strong respectively. Specify as Normal, if the interaction between the phases is between weak and strong.
Courant Number: Courant number is a non dimensional number. It represents the number of cells travelled by a fluid in a time step.
Adaptive Courant Number Method: Algorithm to adapt the time step locally to meet the required CFL condition. The time step is corrected upto the maximum allowed Courant number.

Converge Criterion: When the correction for the solved variables drops below the specified value, the code will stop (Steady) or move to the next time-step (Transient).
Maximum Courant Number: Controls the size of the sub time-steps, used in the calculation of the transport of the components.

Figure 5.99 - Multiphase conditions

Note: When a template is used, Extended Mode has to be selected for Setup Options to view all the parameters.

The settings for the fluid domain in the Multiphase module are classified under the following categories: