Use Duct Size Calculator

This example shows how to obtain flow parameters and duct parameters for a rectangular duct shape.

Procedure

1. Choose Home tab → HVAC group → Duct Size Calculator.
2. In the Duct Size Calculator dialog box, in the Segments group, the Select Routing Object option is active. Select the routing segment.
3. In the Flow Parameters group, set the values for Flow Rate and Velocity. Example: Flow Rate = 0.005, Velocity = 10.
4. In the Duct Parameters group, select the required duct shape, set the values for Height or Width, and press Enter. Example: Shape = Rectangular, Width = 50.

NX calculates the corresponding values of other fields in the Flow Parameters and Duct Parameters groups.

Example results

Flow Parameters

• Friction Loss = 53.489918
• Velocity Head = 5.098399

Duct Parameters

• Height = 10
• Ratio (w:h) = 5
• Equivalent Dia. = 25.23132
• Area = 500

Note: When you specify a valid value for any of the duct parameters, NX tries to calculate the corresponding values of other fields in the Flow Parameters and Duct Parameters groups if the calculator has sufficient inputs. For rectangular and flat oval ducts, height or width is required as an input duct parameter; circular ducts do not require any input duct parameter.

5. Select the Create Stock on Segments check box if you want to create space reservation stocks of the selected shape and calculated dimensions on the selected segments.
6. Select the Display Flow Parameters on Segments check box if you want to display flow and duct parameters.
7. Click OK to apply flow and duct parameters to all segments.

Related topics

• Learn more: Duct Size Calculator
• Look up more details: Duct Size Calculator dialog box