Examples
Examples
Try the starting example
- Airflow (m³/s)
- 0.8
- Air density (kg/m³)
- 1.2
- User-supplied Darcy friction factor
- 0.02
- Target pressure loss per length (Pa/m)
- 1
- Round duct diameter for supplied friction factor (m)
- 0.415945
- Resulting mean velocity (m/s)
- 5.887454
Try another scenario
- Airflow (m³/s)
- 1.8
- Air density (kg/m³)
- 1.2
- User-supplied Darcy friction factor
- 0.02
- Target pressure loss per length (Pa/m)
- 1
- Round duct diameter for supplied friction factor (m)
- 0.57532
- Resulting mean velocity (m/s)
- 6.924111
Calculation method
Calculation method
Round duct diameter for supplied friction factor (m)
Solve Darcy-Weisbach pressure gradient fρv²/(2D), v=4Q/(πD²), assuming constant supplied f.
Resulting mean velocity (m/s)
Solve Darcy-Weisbach pressure gradient fρv²/(2D), v=4Q/(πD²), assuming constant supplied f.
Symbols and units
- a
- Airflow (m³/s)
- b
- Air density (kg/m³)
- c
- User-supplied Darcy friction factor
- d
- Target pressure loss per length (Pa/m)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- User-supplied measurements and assumptions; Solve Darcy-Weisbach pressure gradient fρv²/(2D), v=4Q/(πD²), assuming constant supplied f. Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
Background reading; this does not imply endorsement or independent review of SumFizz.