The Flownex FAQ

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If you have an active license of Flownex, support is provided by the channel partner you purchased from. 

You can find a list of channel partners here. 

If you are lucky enough to be a PADT customer, you can call us at 480.813.4884 or email flownexsupport@padtinc.com.

You may also be able to find help in this FAQ, the Flownex User Forum, or our blog posts on Flownex. 

A tool with as much breadth and depth of capability as Flownex can be hard to pin down. We call it a thermal-fluid simulation tool, but that is really isn’t deep or detailed enough.

It is:

• A System Level Simulation Environment for Modeling Fluid Thermal Systems
• A 1-D Network Numerical Solver Under the Hood
• A Windows Based Software Program
• An Intuitive User Experience
• A Connected and Open Environment
• A System Modeler
• A Digital Twin Creator
• A Design Tool
• An Optimization Tool
• A Community

This is such a common question we created a page with even more detail here. 

Flownex has a great scripting capability with both Quick Script and Script tools.  Both can be found in the components pane near the bottom of the list. 

Quick Script lets you build the script by clicking on the prided tool. And Script lets you edit the code. 

For more detailed information, see our blog article: “Simple Scripting in Flownex.“

Reach out to your account manager or, if you are supported by PADT, email: flownexsupport@padtinc.com.

Flownex added version control for their models in the 2024 release using the popular Git platform. Users can access the Git tool by going to the executable (C:\Program Files\Flownex SE X.X.X.XXXX\GitClient.exe) or using the Git Client found in the configuration tab of the Flownex GUI. 

Use the client tool to connect to your repository and then use the “Save and Commit” button in Version Control under Configuration. 

We have detailed instructions, with video, in the blog post: 

“Flownex Version Control with GIT Client“

Yes, Flownex has a growing set of ways to connect to structural, thermal, and CFD solvers from Ansys. 

Visit the “Ansys Co-Simulation Page” to learn more. 

Flownex supports a standard model object called a Functional Mockup Unit (FMU) to include Reduced Order Models (ROMs) in your Flownex system. FMU’s are defined by the Functional Mockup Interface (FMU) standard. Many other simulation tools output ROMs in the FMU format, or you can make your own. 

Under Import, use the FMU Immport button to specify your FMU file. Once it is read in, it shows up in the Component Library under “FMI.”  The reset is like a native Flownex component. 

Our blog post, “Importing a ROM into Flownex” shows an example with an Ansys Fluent heat exchanger ROM in a Flownex system. 

Parameter tables are a built-in spreadsheet in the Flownex GUI that lets you set up tables for multiple runs.  Each row in the table is a run and it uses the parameter values on that row for the run. 

1. Set up the connection between the spreadsheet and Flownex with the Parameter Sheet Setup
2. Rename the parameter columns so they make more sense and look better in your report.
3. Use the setup tool to reorder the parameters to match what you want to see. It is a good idea to group different types of parameters this way. 
4. Use Excel-like equations to do math in the sheet, just remember that if you move a column, you have to update your cell references. 
5. Remember to use global parameters in the parameter sheet.

Our blog post, “Flownex Parameter Sheet Tricks,” shows all of these steps with animations. 

Flownex supports the ability to specify a table for “ValueType” for inputs where it makes sense.

The best way to use a table this way is first to get your values defined in your favorite spreadsheet.

Then, in the Scenario add the parameter you want to change and select “Table” for “Value Type.”

Next, copy and paste your table in. 

The blog post, “Using a Table for Transient Actions in Flownex,” gives a great example with animations. 

One of the most common uses for Flownex is to model thermodynamic cycles in fluid-thermal systems.  The XY graph tool in Flownex has some special features that let you plot the temperature (T) versus the specific entropy (S) over time in a TS diagram. 

You do this by adding an XY graph, adding the TS diagram (drag and drop) that you input for the material you are using, then adding the results for the key nodes in your system. 

This is a very visual tool, so the animations in our blog post, “Plotting Thermodynamic Cycles in Flownex,” show the exact steps you follow. 

Sizing pumps for a system is a common engineering task, and Flownex makes what is usually a lengthy trial-and-error process straightforward and quick. 

Here are the basic steps for sizing a pump:

1. Chose the right pump/fan component from the library 
2. Set the speed of the component
3. Set the Mass flow to the desired flow rate
4. Click “Fixed mass flow”
5. Set the “Design for mass flow” parameter to “Change Design.”
6. Run your model. 
7. Flownex will calculate the pump design inputs. 

If you have a pump curve, you can also use that in your model. Here are the steps to add it:

1. Go to the Charts and Lookup Tables pane > Project Database > Flow Solver > Turbos and Pumps
2. Select “Add Category”
3. Give it a name
4. Select “Add new Pump and Fan Chart.”
5. Double-click on the curve to modify the pump curve as needed. 

Our blog post, “Sizing Pumps and Manually Specifying a Pump Curve in Flownex,” shows examples for both processes. 

Although Flownex is a 1-D tool, we find it very handy to import a graphic of the system we are modeling and laying out our network over that image.  

Here are the steps to find the right image, import it, and get it set up as a reference:

1. Choose the right image so the components are not too big or too small on the image. We recommend at least 3,000 pixels on a side, and 10,000 wide by 5,000 high works best. 
2. Right-click on the file in Windows and slectect properties and then the Details tab and note the actual dimensions. 
3. Resize the Flownex canvas to match the image size. 
4. Select the “Style” button in the “Appearance” subcategory and add your image. 

Check out the blog post, “Adding a Background Image in Flownex,” for more details and options. 

Yes. Flownex is fully backward compatible. When loading a project from an older version into a newer release you will also be prompted to create a backup just in case.

Yes.

Flownex can model Gas Mixtures, Liquid Mixtures, Two-Phase Fluid and Gas Mixtures, Particle and Liquid Mixtures (Slurries), and Gas and Liquid Mixtures.

The post, “Creating Mixed Fluids in Flownex,” goes through the process step-by-step. 

Your Flownex project retains a log of actions in the project directory: FlownexProjectName_project/CmdRec/Logs, which may be helpful in understanding what led up to a crash.

One way to help our support team is to send them your Flownex model as an archive so we can debug things on our own computers. 

Here are the steps:

1. Go to the “File” menu
2. Select “Save”
3. Select “Save As”
4. Under “Save as type:” choose “Backup zip file (*.zip)
5. Enter a file name and click save.

Our blog post, “Archiving Flownex Networks to Share with Support,” goes through the process in more detail, with pictures.