Note: If you've chosen this project from the New Project window in the app, it's pre-configured with CAD or mesh files, settings, pre-run simulations, visualization filters, and more.
Use this guide to create this case from scratch with a blank project.
A Francis turbine is a type of reaction turbine used in hydroelectric power plants. This tutorial specifically uses the test case provided by NTNU – Norwegian University of Science and Technology under the Francis-99 workshop series. The Francis-99 workshop is initiated by the NTNU and Lulea University of Technology (LTU) in order to further validate the capabilities of CFD technologies.
This mesh is made up of four separate volumes: draft tube, distributor, spiral casing, and runner blades. As high-pressure water enters the spiral casing from the inlet, it forces the runner blades to spin.
The rotation of the runner blades is defined with a reference frame and interfaces between the stationary and rotating components. Interface 1 connects the spiral casing to the distributor, Interface 2 connects the runner to the draft tube, and Interface 3 connects the distributor to the runner.
Note: We recommend exploring how the reference frame and interfaces are set up in the control panel after uploading the settings file or selecting the pre-built version of this project from the New Project window.
Project Files
Project Files
Set Up the Simulation
Download the above mesh and settings files (expand Project Files).
Create a new blank project.
Upload the mesh file.
Upload the settings file. Click the three dot (...) menu at the top of the control panel and select Upload Settings, then select the file from your file browser.
Important: Running this simulation without stopping conditions will increase the credit spend. To view a pre-built version of this project with a pre-run simulation without spending credits, select this project from the New Project window. Learn more about sample projects here.
Create Outputs
Click the + symbol next to the Outputs section in the control panel.
Select Surface.
Set Quantity to Total Pressure Drop.
Scroll down and click inside the IN Surfaces box to enter selection mode.
Select the Inlet surface from the Geometry panel.
Repeat steps 4 and 5 for the OUT Surfaces box, but select the Outlet surface.
Repeat steps 1-3 to create another output, but select Moment from the Quantity list.
Set Moment Axis to 0,0,1.
Scroll down and click inside the Surfaces box.
Select the Runner surface group from the Geometry panel.
Set Stopping Conditions
In the control panel, click Stopping Conditions.
In the properties panel, click + Add Stopping Condition.
Set Output Name to Total Pressure Drop, then set the following parameters:
Averaging Iterations: 100
Iterations to Consider: 5
Click on + Add Stopping Condition to create a second stopping condition.
Set Output Name to Moment, then set:
Averaging Iterations: 100
Iterations to Consider: 5
At the top of the control panel, click Run Simulation.
Apply Visualizations
Use a combination of Streamlines and MultiSlices to visualize the flow through the turbine.
Streamlines
Click on the Streamlines icon
in the Visualization toolbar.In the properties panel, set the parameters as shown below:
Now create a second Streamlines filter:
Make sure to deselect the visualization filter you just created by clicking on any other section in the control panel. Leaving the previous Streamlines filter selected will nest the two filters.
Click on the Streamlines icon
in the Visualization toolbar.In the properties panel, set the parameters as shown below:
MultiSlices
Click on the Slice icon
and select MultiSlice 
in the Visualization toolbar.In the properties panel, set the following:
Now create a second MultiSlice filter:
Make sure to deselect the visualization filter you just created by clicking on any other section in the control panel. Leaving the previous MultiSlice filter selected will nest the two filters.
Click on the Slice icon
and select MultiSlice in the Visualization toolbar.In the properties panel, set the following:
Finally, hide surfaces and adjust the color bars to view the streamlines:
In the Geometry panel, hide the Outlet, Distributor, Spiral Casing, and Draft Tube by hovering over each one and clicking the eye symbol to the right.
Click on the Velocity color bar in the 3D Viewer and adjust Max to 3. Click Done.
Click on the Absolute Pressure color bar and change the Colormap to Viridis. Click Done.
