Cum se calculează Poiseuille Law
Ce este Poiseuille Law?
Poiseuille's law quantifies laminar flow through cylindrical pipes. It shows how flow rate depends on pressure, pipe dimensions, and fluid viscosity.
Formulă
The calculator applies Q = (π × ΔP × r⁴) / (8 × η × L)
- Q
- (π × ΔP × r⁴) / (8 × η × L) — (π × ΔP × r⁴) / (8 × η × L)
- L
- L value — Variable used in the calculation
Ghid pas cu pas
- 1Enter pressure difference, pipe radius, length, and dynamic viscosity
- 2The calculator applies Q = (π × ΔP × r⁴) / (8 × η × L)
- 3Results show volumetric flow rate
Exemple rezolvate
Intrare
ΔP = 1000 Pa, r = 1 mm, L = 1 m, η = 0.001 Pa·s (water)
Rezultat
Q ≈ 0.39 mL/s
Surprisingly slow
Greșeli frecvente de evitat
- ✕Forgetting to use radius, not diameter, in the r⁴ term
- ✕Confusing dynamic viscosity (Pa·s) with kinematic viscosity (m²/s)
Întrebări frecvente
Why is flow proportional to r⁴?
Small radius changes dramatically affect flow; doubling radius increases flow 16×, which is why plumbing uses large pipes.
How does viscosity affect flow?
Higher viscosity reduces flow; thick oils flow much slower than water at the same pressure difference.
Ești gata să calculezi? Încercați calculatorul gratuit Poiseuille Law
Încercați singur →