Fluid-Fluid Interfaces

Fluid-fluid interfaces exist when your simulation contains different fluid regions in contact with one another or a single fluid region that comprises more than one body. For example, Discovery automatically creates a fluid-fluid interface if one of the fluid regions is a rotating zone or in simulations containing additional bodies as locations for porous conditions. Additionally, multiple bodies might be used to allow for the local refinement of the mesh in Refine.

Reviewing the fluid interface allows you to control the detection distance and visually diagnose the overlapping interfaces or conversely check that the interface does exist where it is expected. Decreasing the detection distance enforces a tighter tolerance for detecting whether faces are touching or not. Using a smaller detection distance usually removes any spurious faces that may be overlapping with another condition or interface.

To review your fluid-fluid interfaces, go to File > Settings > Physics and under Workflow Options select Show fluid-to-fluid interfaces. You must restart Discovery for the change to take effect. See Reviewing Fluid-Fluid Interfaces for more information.