## 6.2. Setting up a Transient Blade Row Model

You can use the Turbomachinery wizard in CFX-Pre to set up a Transient Blade Row model.

1. Under the Basic Setting Panel set the Analysis Type to `Transient Blade Row`; and select either the `Time Transformation` or `Fourier Transformation` option under Method.

2. Define the rotor and/or stator blade passages under Components Definition.

   When using the Fourier Transformation method, you must set up two blade passages per component and adjust the periodic interfaces accordingly. You must set the Passages and Alignment > Passages/Mesh > Passages to Model to `2`. This will also create the Sampling Interface required for the Fourier Transformation model.

3. Set up the physics as usual (including domains, domain interfaces, boundary conditions, and so on, as required) under the Physics Definition panel.

4. Under the Interface Definition panel you can observe and modify the various sampling and periodic interfaces that are automatically generated by the TurboMachinery wizard.

5. Under the Disturbance Definition panel, you will specify the periodicity of the disturbance being imposed.

6. Continue clicking Next until the Final Operations panel is reached. Set Operation to `Enter General Mode` because you will continue to define the simulation through settings not available in the TurboMachinery wizard.

7. Ensure that there is a `Transient Blade Row Models` object under the applicable Flow Analysis object. If there is not, you can add one according to the instructions provided at Inserting a New Transient Blade Row Models Object in the CFX-Pre User's Guide.

8. Configure the settings in the details view for the Transient Blade Models object. For details, see Transient Blade Row Models Details View in the CFX-Pre User's Guide.

9. Configure the output control settings. These settings are described at Transient Blade Row Results in the CFX-Pre User's Guide. It is a good practice to set up monitor points to check the results. For details, see Setting up Monitors to Check Results.

For details, see Starting a New Case in Turbo Mode in the CFX-Pre User's Guide.

The procedure for setting up a Transient Blade Row model in General mode is as follows:

1. Set the analysis type to `Transient Blade Row`; also set the initial time.

   For details, see Analysis Type Settings in the CFX-Pre User's Guide.

2. Set up the physics as usual (including domains, domain interfaces, boundary conditions, and so on, as required).

   In particular, you must set the External Passage Definition settings (Passages in 360 and Pass. in Component) on the Basic Settings tab for each domain.

   When using the Fourier Transformation method, you must set up two blade passages per component and adjust the periodic interfaces accordingly. The interface(s) between passages must use a GGI connection.

3. Ensure that there is a `Transient Blade Row Models` object under the applicable Flow Analysis object. If there is not, you can add one according to the instructions provided at Inserting a New Transient Blade Row Models Object in the CFX-Pre User's Guide.

4. Configure the settings in the details view for the Transient Blade Models object. For details, see Transient Blade Row Models Details View in the CFX-Pre User's Guide.

5. Configure the output control settings. These settings are described at Transient Blade Row Results in the CFX-Pre User's Guide. It is a good practice to set up monitor points to check the results. For details, see Setting up Monitors to Check Results.

You can change an existing transient case to use Transient Blade Row models in General mode as follows:

1. Change the analysis type to `Transient Blade Row`.

   For details, see Analysis Type Settings in the CFX-Pre User's Guide.

2. Set the External Passage Definition settings (Passages in 360 and Pass. in Component) on the Basic Settings tab for each domain.

3. When using the Fourier Transformation method, you must set up two blade passages per component and adjust the periodic interfaces accordingly. The interface(s) between passages must use a GGI connection.

4. Ensure that there is a `Transient Blade Row Models` object under the applicable Flow Analysis object. If there is not, you can add one according to the instructions provided at Inserting a New Transient Blade Row Models Object in the CFX-Pre User's Guide.

5. Configure the settings in the details view for the Transient Blade Models object. For details, see Transient Blade Row Models Details View in the CFX-Pre User's Guide.

6. Configure the output control settings. These settings are described under Transient Blade Row Results in the CFX-Pre User's Guide. It is good practice to set up monitor points to verify that a periodic solution has been achieved. For details, see Setting up Monitors to Check Results.

Note that a given simulation can use either the Time Transformation or Fourier Transformation model, but not both. Either of these models can be used in conjunction with the Profile Transformation model. The Profile Transformation model, when used in conjunction with one of the other methods, is not explicitly selected in the user interface. For details on the Profile Transformation model, see Profile Transformation.

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