Hello Patil

The Darcy Equation is a theoretical equation that predicts the frictional energy loss in a pipe based on the velocity of the fluid and the resistance due to friction. It is used almost exclusively to calculate head loss due to friction in turbulent flow.

The Darcy friction factor, f, is usually selected from a chart known as the Moody diagram. The Moody diagram is a family of curves that relate the friction factor, f, to Reynolds number, Re, and the relative roughness of a pipe,e/D.

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