Gravity Pipe Flow Calculator [extra Quality] May 2026

[ Q = \frac1n \cdot A \cdot R^2/3 \cdot S^1/2 ]

Here is comprehensive content about a , suitable for a website, engineering tool description, or educational resource. Gravity Pipe Flow Calculator What Is Gravity Pipe Flow? Gravity pipe flow occurs when a liquid—typically water, sewage, or storm runoff—flows through a pipe without pressure . The movement is driven solely by the slope (gradient) of the pipe and the force of gravity, not by pumps or external pressure.

| Input | Description | Example | |-------|-------------|---------| | | Inside diameter | 12 inches (or 300 mm) | | Pipe slope | Rise over run | 1% (0.01 ft/ft) | | Manning's n | Pipe roughness | Concrete: 0.013, PVC: 0.009, Corrugated metal: 0.024 | | Flow depth ratio | Depth / Diameter (0 to 1) | 0.75 (75% full) |