Improved method of determining friction factor in pipes

Abstract

Purpose – The purpose of this paper is to present an improved computational method for determining the friction factor for turbulent flow in pipes. Design/methodology/approach – Given that the absolute pipe roughness is generally constant in most systems, and that there are few changes to the pipe diameter, the proposed method uses a simplified equation for systems with a specific relative pipe roughness. The accuracy of the estimation of the friction factor using the proposed method is compared to the values obtained using the implicit Colebrook-White equation while the computational efficiency is determined by comparing the time taken to perform 300 million calculations. Findings – The proposed method offers a significant improvement in computational efficiency for its accuracy and is compared 28 of the explicit equations currently in use. Practical implications – This method enables a simplified equation to offer a significant improvement in computational efficiency for its accuracy and is easier to code, enabling engineers to more efficiently calculate frictional pressure loss for flow in pipes. Originality/value – Due to the complexities in flow regime and pipe roughness, there is a limit to the scope for further computational efficiency through simplification of the explicit equation. This paper presents a new method and simplified equation which combined are able to deliver results with similar accuracy to less computationally efficient explicit equations.