### 5.5.1. Tips on Using ANSYS Workbench

The following sections contain tips for the general use of ANSYS CFX in ANSYS Workbench:

#### 5.5.1.1. ANSYS Workbench Interface

A lot of important functionality is available in the context menu (cells, parameter bar, and so on). Also, you should enable the View > Properties view and investigate options for each cell.

Compact Mode is very useful. It turns the schematic into a small non-intrusive button that is always on top, effectively replacing the need for the toolbar navigation.

#### 5.5.1.2. Setting Units

ANSYS Workbench units and options are not passed to ANSYS CFX applications; this could require you to set units twice.

#### 5.5.1.3. Files View

Use the Files view to determine which files were created for each cell/system. This can be very useful if you need to do some runs or change some settings outside of ANSYS Workbench, or if you want to manually delete some but not all files associated with a particular cell. It is easiest to find files associated with a specific cell by sorting the view by Cell ID. This will sort the list by system and then by cell.

#### 5.5.1.4. ANSYS Workbench Preferences: Named Selections

The default setting in Workbench for Named Selection is `off`, and a filter prefix is specified, in the Tools > Options > Geometry Import settings. In order to make sure that `Named Selections` specified in DesignModeler propagate through to the meshing stage, you need to enable Named Selections and clear the Filtering Prefixes.

Note: If you select a language other than English under Regional and Language Options in ANSYS Workbench, use of Symmetry and Enclosure operations in DesignModeler can lead to special characters (e.g. Umlauts in German, which are not supported for use in ANSYS CFX) being included in automatically generated `Named Selections`. You can prevent such `Named Selections` from being created by either:

- Using Meshing as part of a `Fluid Flow (CFX)` system (rather than a separate Mesh component system)

- Changing the Advanced Geometry Option > Enclosure and Symmetry Processing, under the Geometry cell properties, from the default `Yes/On` to `No/Off`.

#### 5.5.1.5. Mesh Modifications in CFX-Pre in ANSYS Workbench

If you perform any mesh modifications (such as transformations, renaming, glue/unglue, delete) within CFX-Pre on meshes provided by the project schematic, avoid any further changes to the Mesh and Geometry cells providing these meshes.

During a refresh of upstream mesh data, CFX-Pre will require that the same series of mesh modifications and transformations on the new mesh be successfully reapplied. If any of these transformations fail (possibly due to topological changes, or changes to regions and named selections that the transformations operate on), CFX-Pre will issue an error message, and revert to the previous mesh data. Workbench will report the error as an "Application Error" during the mesh refresh, however the project schematic state for the Setup cell will indicate that the refresh was done successfully by being marked as Up-to-date.

To correct this mesh refresh error, the geometry or mesh changes that caused the error should be reverted, or (if possible) the Mesh cell should be disconnected and the Setup cell refreshed again before reconnecting the Mesh cell.

#### 5.5.1.6. Loading .cmdb Files

To import a .cmdb file, you have to use the File > Import option on the main ANSYS Workbench toolbar. This will import the geometry and mesh settings and create a .mshdb file.

It is not possible to read a mesh file without any reference to a geometry file, even when you select File > Import and select a .cmdb file. A Mesh system that includes a Geometry cell appears (the Geometry cell has a green tick and a red circle with "!"). If you try to link or duplicate such a system, problems are observed.

It is also not possible to read a mesh file without any reference to a geometry file when creating a mesh component system first – you cannot right-click the Mesh cell and select a command to import a .cmdb file; only .gtm and .cfx files are possible choices.

#### 5.5.1.7. ANSYS Workbench Connections

When selecting a system in the toolbox, ANSYS Workbench will highlight the cells in any systems already in the Project Schematic to which a valid connection can be made.

Connections between systems in ANSYS Workbench are direction-dependent. This has implications in one-way and two-way FSI cases. For example, in a one-way case you need to transfer the data from the CFX system to the Static Structural system. As a consequence, the CFX system will be positioned to the left of the Static Structural system on the schematic. For two-way FSI, the Static Structural system will be positioned to the left of the CFX system on the schematic.

Connections are not supported from the Setup cells of Steady-State and Transient Thermal analyses systems to the Setup cell of the Fluid Flow systems (for example, thermal two-way FSI).

Using multi-configuration CFX cases as part of a one-way FSI calculation is not supported. The project schematic will permit the connection, but the calculation will fail.

Release 18.2 - © ANSYS, Inc. All rights reserved.