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Isothermal Pipe Flow Calculator































How This Is Calculated


$$ p_2 = p_1 \sqrt{1 - \frac{4f {u_1}^2 L}{R T d} - \frac{2 {u_1}^2}{RT} ln \left(\frac{p_1}{p_2}\right) } $$ where:

p2   =   Pressure at point 2   (Pa)

p1   =   Pressure at point 1   (Pa)

f   =   Darcy-Weisbach friction factor   (dimensionless)

u1   =   Average fluid velocity   (m/s²)

L   =   Length of pipe   (m)

R   =   Specific gas constant   (j/kgK)

T   =   Absolute temperature   (K)

d   =   Diameter of the pipe   (m)


Assumptions


  • The fluid is incompressible and Newtonian.
  • The fluid is in a steady flow.
  • The fluid flow is laminar.
  • The cross-section is uniform.
  • There is no heat transfer.
  • The pipe is ideal (i.e., there is no friction from roughness or imperfections).


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