Reynolds Number
Compare inertia and viscosity in an entered flow scale.
Your numbers
Reynolds number
Characteristic length and transition thresholds depend on geometry; this tool does not classify every flow with a pipe-only threshold.
Scenario comparison
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Formula
Re=ρvL/μ
Compare inertia and viscosity in an entered flow scale.
Worked example
- Density (kg/m³)
- 1000
- Mean speed (m/s)
- 1
- Characteristic length (m)
- 0.01
- Dynamic viscosity (Pa·s)
- 0.001
- Reynolds number
- 10,000
Scope and limitations
Characteristic length and transition thresholds depend on geometry; this tool does not classify every flow with a pipe-only threshold.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: 6bfdc01cd87f · Example checked: