Explicit Reformulation of the Colebrook−White Equation for Turbulent

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Ind. Eng. Chem. Res. 2007, 46, 2593-2600

2593

Explicit Reformulation of the Colebrook-White Equation for Turbulent Flow Friction Factor Calculation Jagadeesh R. Sonnad Department of Radiological Sciences, UniVersity of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73190

Chetan T. Goudar* Bayer HealthCare, Biological Products DiVision, 800 Dwight Way, B55-N, Berkeley, California 94710

In this paper, we present an improvement of a mathematically equivalent representation of the ColebrookWhite (CW) equation to compute friction factors for turbulent flow in rough pipes. This new form is simple and very well-suited for accurately estimating the friction factor, because no iterative calculations are necessary. Specifically, the friction factor is expressed as the sum of known simple functions and an unknown correction term. This correction term satisfies an auxiliary equation that can be accurately and easily solved with predictable error bounds over the complete range of pipe roughness and Reynolds number values encountered in practice. The simplest case, with the unknown correction term set to zero, resulted in friction factor estimates with errors of