EngiRef / Fluids Engineering Formula
Reynolds Number
Reynolds Number: Dimensionless number indicating laminar or turbulent flow. A Fluid Dynamics formula in fluids engineering. Variables Re, ρ, v, D and μ, each…
Fluid Dynamics
Specification
- Name
- Reynolds Number
- Discipline
- fluids
- Category
- Fluid Dynamics
- LaTeX
- Re = \frac{\rho vD}{\mu}
- Description
- Dimensionless number indicating laminar or turbulent flow
- Conditions
- Internal flow in circular pipes: laminar <~ 2300, turbulent >~ 4000
- Can solve for
- Re, ρ, v, D, μ
- Tags
- reynolds, laminar, turbulent, flow
Variables
| Symbol | Name | Unit | Si Unit | Imperial Unit |
|---|---|---|---|---|
| Re | Reynolds Number | — | — | — |
| ρ | Density | kg/m³ | kg/m³ | slug/ft³ |
| v | Velocity | m/s | m/s | ft/s |
| D | Characteristic Length | m | m | ft |
| μ | Dynamic Viscosity | Pa·s | Pa·s | — |