This section describes the typical workflow of using the Eulerian Wall Film (EWF) model to simulate thin liquid films.
The use of the Eulerian Wall Film model involves the following steps:
Enable and setup relevant Ansys Fluent models that are compatible with the Eulerian Wall Film model. Ansys Fluent models that are not compatible with the Eulerian Wall Film model are outlined in Limitations.
Enable the Eulerian Wall Film model and set the model option as described in Setting Eulerian Wall Film Model Options. Note that certain options are only available when the relevant Ansys Fluent models are enabled.
Set the wall film solution controls as described in Setting Eulerian Wall Film Solution Controls.
For each wall where you want to model the Eulerian wall film, assign appropriate boundary conditions as described in Setting Eulerian Wall Film Boundary, Initial, and Source Term Conditions.
If necessary, solve the flow field first to establish a sound flow field before enabling the wall film solution.
Initialize and solve the film flow. Note that the wall film model can be initialised along with the flow field initialisation, or over an existing flow field from the Eulerian Wall Film dialog box (Model Options and Setup tab) as described in Setting Eulerian Wall Film Model Options.
Examine the film solution results. For information about available wall film postprocessing variables, refer to Postprocessing the Eulerian Wall Film.
Performing Mesh and Zone operations during wall film solution process:
Any mesh and zone operations, such as Make Polyhedra, Combine, and Separate, should be performed prior to setting up the Eulerian Wall Film model whenever possible. These operations impact the wall film model in the following ways:
For the Make Polyhedra operation, the Eulerian Wall Film model and all assigned wall film conditions will be disabled before the polyhedral mesh conversion and enabled automatically after the operation is complete. All existing wall film data will be discarded.
For the cell zone Merge and Separate operations, the Eulerian Wall Film model and all assigned wall film conditions will be disabled and will require manually enabling afterwards. Warnings will be issued before and during the operations. All existing wall film data will be discarded.
For the face zone Merge and Separate operations, the Eulerian Wall Film model will remain enabled. However, assigned wall films on walls involved in the face merge and separation will be disabled and will need to be manually enabled afterwards. The film model must be re-initialised after the face operation is complete. All existing wall film data will be discarded.
Mesh Adaption during wall film solution process:
The Eulerian Wall Film model is compatible with the mesh adaption. Wall film data is preserved during the adaption process. However, certain wall film model setups, such the VOF coupling transition criteria, may need to be adjusted to reflect the changes in mesh resolution.