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Pipe mean flow velocity
Find mean liquid speed from circular bore diameter and volume flow.
A clear answer. Here’s how.
Uses the full internal circular area πD²/4 and mean velocity=Q/A. Converts millimetres and litres/minute to SI internally. Assumes a completely filled pipe; velocity is the section average rather than the centreline peak. Does not infer pressure loss, roughness or partial-depth flow.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Internal bore diameter (mm)
- 25
- Volume flow (L/min)
- 20
Example result
- Mean velocity (m/s)
- 0.679061090525
- Flow cross-section (m²)
- 0.000490873852123
- Volume rate (m³/s)
- 0.000333333333333