Πώς να υπολογίσετε το Reynolds Number

Τι είναι το Reynolds Number;

The Reynolds number (Re) predicts whether fluid flow is laminar (smooth, Re < 2,300) or turbulent (chaotic, Re > 4,000). It is dimensionless and fundamental to fluid dynamics.

Τύπος

Re

Reynolds number (dimensionless)

ρ

Fluid density (kg/m³)

v

Flow velocity (m/s)

L

Characteristic length (m)

μ

Dynamic viscosity (Pa·s)

ν

Kinematic viscosity (m²/s)

Οδηγός βήμα προς βήμα

1. 1Re = ρ × v × d / μ
2. 2ρ = density (kg/m³); v = velocity (m/s); d = diameter (m); μ = dynamic viscosity (Pa·s)
3. 3Water at 20°C: μ ≈ 0.001 Pa·s
4. 4Air at 20°C: μ ≈ 1.81×10⁻⁵ Pa·s

Worked Examples

Frequently Asked Questions