Calculate pressure drop, flow rate, or pipe dimensions for laminar fluid flow.
Flow Parameters
Calculation Results
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Overview
Poiseuille's Law describes the pressure drop in an incompressible and Newtonian fluid in laminar flow through a long cylindrical pipe of constant cross-section.
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Pro Tips
The law only applies to laminar flow (Re < 2300).
Notice the R⁴ term: doubling the pipe radius reduces pressure drop by a factor of 16 for the same flow!
Viscosity (μ) depends heavily on temperature.
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Fun Facts
"Jean Léonard Marie Poiseuille was a French physicist and physiologist interested in blood flow."
"The law is fundamental to understanding hemodynamics in the human circulatory system."
"The SI unit of dynamic viscosity is Pascal-second (Pa·s)."
