Hagen–Poiseuille Law

Written by Jerry Ratzlaff on . Posted in Thermodynamics

Hagen–Poiseuille Law, also called Poiseuille Law, Poiseuille Equation or Hagen–Poiseuille Equation, gives the pressure loss in a fluid flowing through a long cylindrical pipe.

Hagen–Poiseuille Law Formula

\(\large{ \Delta p = \frac { 8 \; \mu \; l \; Q }{ \pi \; r^4 }   }\)

\(\large{ \Delta p = \frac { 128 \; \mu \; l \; Q }{ \pi \; d^4 }   }\)

Where:

\(\large{ \Delta p }\) = pressure loss

\(\large{ \mu }\)  (Greek symbol mu) = dynamic viscosity

\(\large{ l }\) = length

\(\large{ Q }\) = volumetric flow rate

\(\large{ \pi }\) = Pi

\(\large{ r }\) = radius

\(\large{ d }\) = diameter

 

Tags: Equations for Pressure Equations for Pipe