Reynolds Number Calculator
Determine flow regime: Laminar, Transient, or Turbulent.
Input Parameters
Enter fluid properties and pipe geometry (SI Units).
Water ≈ 1000 kg/m³, Air ≈ 1.225 kg/m³
Water ≈ 0.001 Pa·s (at 20°C)
What is Reynolds Number?
The Reynolds number (Re) is a dimensionless quantity that helps predict flow patterns in different fluid flow situations.
- Re < 2000: Laminar Flow (Smooth, constant fluid motion)
- 2000 < Re < 4000: Transitional Flow
- Re > 4000: Turbulent Flow (Chaotic, eddies)
Formula
Re = (ρ v D) / μ
ρ = Density (kg/m³)
v = Velocity (m/s)
D = Diameter (m)
μ = Dynamic Viscosity (Pa·s)