Major Loss Calculation for Fluid Flow using Darcy-Weisbach Friction Loss Equation

To: LMNO Engineering home page Design of Circular Pipes Calculator Unit Conversions Trouble printing?

Major Loss Equations

Your browser does not support Java, or Java is disabled in your browser. Calculation should be here.

g = acceleration due to gravity = 32.174 ft/s² = 9.806 m/s²

Major loss (h_f) is the energy (or head) loss (expressed in length units - think of it as energy per unit weight of fluid) due to friction between the moving fluid and the duct. It is also known as friction loss. The Darcy-Weisbach method is generally considered more accurate than the Hazen-Williams method. Additionally, the Darcy-Weisbach method is valid for any liquid or gas; Hazen-Williams is only valid for water at ordinary temperatures (40 to 75 ^oF). The Hazen-Williams method is very popular, especially among civil engineers, since its friction coefficient (C) is not a function of velocity or duct diameter. Hazen-Williams is simpler than Darcy-Weisbach for calculations where you are solving for flowrate, velocity, or diameter. More Discussion and References.

LMNO Engineering, Research, and Software, Ltd.
7860 Angel Ridge Rd. Athens, Ohio USA (740) 592-1890
LMNO@LMNOeng.com http://www.LMNOeng.com