Empirical Relation between Hazen-Williams and Darcy-Weisbach Equations for Cold and Hot Water Flow in Plastic Pipes
Rehan Jamil* and M. Abdul Mujeebu**
Department of Building Engineering, College of Architecture and Planning, Imam Abdulrahman Bin Faisal University, P. O. Box 1982, Dammam 31441, Saudi Arabia
*Email: rjamil@iau.edu.sa, **E-mail: mmalmujeebu@iau.edu.sa
Keywords: empirical relation; Darcy-Weisbach; Hazen-Williams; water supply; plastic pipes; fluid dynamics
Received: October 10, 2018; Revised: December 20, 2018; Accepted: January 9. 2019; Published: February 1, 2019; Available Online: February 1, 2019
Abstract
This article presents an empirical relation between Darcy-Weisbach and Hazen-Williams equations, for cold and hot water flows through plastic pipes. Corresponding to water temperatures ranging from 20ºC to 60ºC, five hydraulic models were developed to estimate the head loss in the pipes for various pipe diameters (15 mm to 50 mm) and volume flowrates (0.25 lps to 2 lps). The head loss values obtained by the Darcy-Weisbach and Hazen-Williams equations were used to establish the correlation between them. The correlation coefficient between both equations was found to be 0.999, while the R2 value for the trend-line of head loss values obtained by these equations was 0.9993. This relationship would be very useful for the manufacturers and designers for the mutual conversion of head loss values obtained by these equations.