A brief review of experimental friction loss studies for polyetylene pipes

Abstract

Plastic pipes, especialiy polyethylene pipes have grown to become one of the freguently utilized material in pipeline systems owing to its advantages of corrosion, biological and chemical resistance over traditional metal pipes. Similar to any other material, design of polyethylene pipeline system reguires a comprehensive and detailed friction head loss analysis. There are two main methods on the literature recommended for estimating friction head loss. One is the weli-known Darcy-Weisbach eguation and the other is an empirical formula known as Hazen-Williams eguation. Darcy-Weisbach eguation depends on Darcy friction factor and Hazen-Williams eguation depends on Hazen-Williams coefficient. To estimate Darcy friction factor, pipe roughness height must be known. In the recent studies, head losses in polyethylene and plastic pipes are commonly estimated by using some constant coefficienis for pipe roughness height and Hazen-William formula. However, the experimental studies revealed that these values have a strong dependence on varying pipe diameter and flow regime characterized by Reynolds numbers. Therefore, a single fixed value cannot be used for ali ranges of diameters and flow velocity on polyethylene pipelines. In this paper, ihe authors reviewed ihe experimental studies for friction loss on polyethylene pipes and recommended some methods to hydraulic design of polyethylene pipeline systems. The results indicated the shortage of experimental studies for plastic pipes, particulariy for higher ranges of polyethylene pipe sizes.