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Poiseuille's law quantifies laminar flow through cylindrical pipes. It shows how flow rate depends on pressure, pipe dimensions, and fluid viscosity.

सूत्र

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

चरण-दर-चरण मार्गदर्शिका

  1. 1Enter pressure difference, pipe radius, length, and dynamic viscosity
  2. 2The calculator applies Q = (π × ΔP × r⁴) / (8 × η × L)
  3. 3Results show volumetric flow rate

हल किए गए उदाहरण

इनपुट
ΔP = 1000 Pa, r = 1 mm, L = 1 m, η = 0.001 Pa·s (water)
परिणाम
Q ≈ 0.39 mL/s
Surprisingly slow

सामान्य गलतियां जिनसे बचना है

  • Forgetting to use radius, not diameter, in the r⁴ term
  • Confusing dynamic viscosity (Pa·s) with kinematic viscosity (m²/s)

अक्सर पूछे जाने वाले प्रश्न

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.

सेटिंग्स