EngiRef / Fluids Engineering Formula
Hagen-Poiseuille Equation
Hagen-Poiseuille Equation: Volumetric flow rate for laminar pipe flow. A Pipe Flow formula in fluids engineering. Variables Q, ΔP, d, μ and L, each with SI and…
Pipe Flow
Specification
- Name
- Hagen-Poiseuille Equation
- Discipline
- fluids
- Category
- Pipe Flow
- LaTeX
- Q = \frac{\pi \Delta P d^4}{128 \mu L}
- Description
- Volumetric flow rate for laminar pipe flow
- Conditions
- Laminar flow (Re < 2300), fully developed
- Can solve for
- Q, ΔP, d, L
- Tags
- hagen, poiseuille, laminar, flow, viscous
Variables
| Symbol | Name | Unit | Si Unit | Imperial Unit |
|---|---|---|---|---|
| Q | Flow Rate | m³/s | m³/s | ft³/s |
| ΔP | Pressure Drop | Pa | Pa | psi |
| d | Pipe Diameter | m | m | in |
| μ | Dynamic Viscosity | Pa·s | Pa·s | — |
| L | Pipe Length | m | m | ft |