Haaland equation

In fluid dynamics, the Darcy friction factor formulae are equations that allow the calculation of the Darcy friction factor, a dimensionless quantity used in the Darcy –Weisbach equation , for the description of friction losses in pipe flow as well as open-channel flow. The Darcy friction factor is also known as the Darcy– Weisbach . Haaland of the Norwegian Institute of Technology. Rapporter et annet bilde Rapporter det støtende bildet. It 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, but the discrepancy from experimental data is well . Because of the iteration new equations to solve this friction factor has been developed.

Absolute Roughness Ks = 1. Internal Bore Diameter d = 0. The determination of a single-phase friction factor of. Reference to a graph can sometimes be inconvenient especially when a computer is being used to make calculations. It is therefore desirable to have curve fit equations for the Moody diagram. It is important to understand which friction factor is being described in an equation or chart to prevent error in pressure loss, or fluid flow calculation.

The equation is recommended for use in the oil and gas industry. Some of the Colebrook-White equation approximation formulas are listed below. A good approximate equation shown. The minor loss representations, K and C in Equation 3. VercOme this difficulty.

The Chen equation is valid f0r . Finally, Swamee and Jain . The textbook by Welty et al. Colebrook equation calculator solving for Darcy friction factor given absolute roughness, diameter and Reynolds number.