REVIEW ARTICLE
Why the Fluid Friction Factor should be Abandoned, and the Moody Chart Transformed
Eugene F. Adiutori *
Article Information
Identifiers and Pagination:
Year: 2009Volume: 3
First Page: 43
Last Page: 48
Publisher Id: TOMEJ-3-43
DOI: 10.2174/1874155X00903010043
Article History:
Received Date: 29/11/2008Revision Received Date: 27/01/2009
Acceptance Date: 12/03/2009
Electronic publication date: 11/6/2009
Collection year: 2009
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
The “fluid friction factor” (f) should be abandoned because it is a mathematically undesirable parameter that complicates the solution of fluid flow problems.
f is the dimensionless group πgPD/8LW. This group is mathematically undesirable because it includes ΔP, W, and D. Therefore if f is used in the solution of a problem, the problem must be solved with ΔP, W, and D in the same term, even though fluid flow problems are generally much easier to solve if ΔP, W, and D are in separate terms. (Just as it is generally much easier to solve equations if x and y are in separate terms).
The mathematical complication introduced by f is illustrated by the Moody chart (Fig. 1). Because the chart is based on f, it must be read iteratively (or by trial-and-error) to determine W or D. But if the Moody chart is transformed in order to eliminate f, the transformed chart (Fig. 2) is read directly to determine ΔP, W, or D.
The fluid flow methodology described herein altogether abandons f, and allows fluid flow problems to be solved in the simplest possible manner.
