Fluid Stream Setup

Step 1: Create Primitive Geometry

This will create a model whose size is below 300 nodes, allowing new users to gain experience with a demo license of RadTherm/WinTherm/MuSES.

• Create elbow primitive from Create tab on the Geometry main tab.
• Under Elbow Parameters, type "16" for number of elements along length and "8" for around diameter.

Step 2: Create a Fluid Stream

Next we will create a fluid stream. The fluid stream will be put inside of the swept elbow. It will flow down the length and will have a number of fluid thermal nodes spaced along the interior of this pipe.

• Select the Name List under Part Selector, and rename "new elbow" as "pipe."
• We will now set up the fluid streams. First, we need to create a fixed temperature source.
• Click the Add Part button; then rename the part "fluid_source" in the Name List.

Step 3: Changing the Temperature

This will assign a specific temperature to our fluid source.

• Click on the Editor Tab.
• Change Temperature to Assigned.
• Change the Value of Temperature to 300.

Step 4: Create a Fluid Stream

First we will create a Fluid Stream.

• Click the Add Part button.
• Select Fluid Stream from the Part Type pull-down list.
• Rename the Fluid Stream part to "Fluid_Stream."

Step 5: Connect Fluid Stream to Fluid Source

The Fluid Stream needs to be connected to the Fluid Source. We will connect it to the interior of the pipe's geometry.

• Under Advection Links, click Add.
• Select Upstream Part, and choose Fluid_Source.
• Select Volume under Flow Type, and enter a Volume of 100 L/min (default).

Step 6: Set the Fluid Stream Boundaries (Inlet)

Next we will set up the boandaries of the fluid stream.

• Under Node Distribution, type 10 as the number of nodes.
• Click the Fluid Stream Boundaries tab.
• Click on the Select Inlet arrow button.

• On the model, click two elements that span the opening of the inlet (elements on opposite sides of the opening). The mid-point between these elements defines the starting point of the fluid inlet.
• Click on a third element on the opening. This will set the direction of the flow. An arrow will appear, representing the direction of the flow.
• If the arrow is pointing out, click Flip Inlet to change the direction of the arrow. This allows our fluid to flow into the elbow.

Step 7: Set the Fluid Stream Boundaries (Outlet)

Now that the Inlet is set up, we will do the Outlet.

• Click on the Select Outlet arrow button.
• Click two elements that span the outlet opening. This will determine the midpoint of the outlet.

We have now defined where the fluid enters and exits the geometry.

Step 8: Determining Physical Boundaries

Next we will establish what parts will be the physical boundaries of the fluid stream.

• Click the Add button under Bounding Parts. The Bounding Part Selection window will appear.
• Click your Pipe part. Click OK.

In this case, we are setting the fluid stream to connect only to the back side of the geometry. The darker color indicates the back side, in this case the interior of the pipe. Care should be taken with your actual models to check for front/back associations.

Step 9: Convection Settings

Now we will check the convection setting for the backside of the pipe assigned to the fluid stream.

• Under the Automatically Update Convection Type For section, click the All Parts button.
• Go back up to the Name List, in the Part Selector section at the top, and select Pipe.
• Click on the Back tab.

• Under Convection Type, Fluid Stream should be selected.
• Go up to the Name List again, and select Fluid Stream. Then at the bottom of that window, click the Generate Fluid Nodes button.

This will generate ten fluid nodes, distributed spatially along the pipe, which represents the fluid stream boundary. The geometry now should be transparent, allowing you to see the interior of the pipe. The fluid nodes each have a distinct volume associated with them and a geometric connection to the elements along the pipe.

Step 10: Run the Simulation

With our fluid stream set up, we can now perform a run with the default steady-state parameters.

• At the top of the window, click the Analyze tab. Then click the Params tab inside that tab.
• Click the Run button at the bottom of the window.
• Name the file, and the solution will commence.
• At the bottom of the display window, click the Autoscale button to view the geometry temperatures.

Step 11: Post Process the Results

• Click on the Post Process tab, then click on an element of the pipe. The elements front and back temperatures are displayed.
• Select the backside thermal node and view the heat rates at the bottom of the window.
• Click on the Boundary Conditions tab and view the predicted convection data.
• Click the Part button in the button bar (under the menu bar). Open the Parts List (Window>Parts List) and select the Fluid Stream part. The data for all 10 thermal nodes will be displayed.