Swamee-Jain equation

From Wikipedia, the free encyclopedia

You have new messages (last change).

The Swamee-Jain equation is used to solve directly for the Darcy-Weisbach friction factor f for a full-flowing circular pipe. It is an approximation of the implicit Colebrook-White equation.

f = \frac{0.25}{[log (\frac{\epsilon}{3.7D} + \frac{5.74}{Re^{0.9}})]^2}

Where f is a function of:

  • roughness height, ε (m, ft)
  • pipe diameter, D (m, ft)
  • Reynolds number, Re (unitless).

The equation was found to match the Colebrook-White equation within 1.0% for 10-6 < ε/D < 10-2 and 5000 < Re < 108.

[edit] Reference

  • 1976, Swamee, P.K. and Jain, A.K., Explicit equations for pipe-flow problems, Journal of the Hydraulics Division, ASCE, 102, HY5, 657-664
Retrieved from "http://en.wikipedia.org../../../s/w/a/Swamee-Jain_equation_28da.html"
In other languages