Elucidating the water-hammer surge behaviour in steel / high and low density PolyEthylene -based piping systems

Abstract

ABSTRACT The in-series connections of multi-pipes involving steel and polymeric materials were identified as being an effective design tool to extenuate water-hammer surges induced into an existing steel-main pipe-based hydraulic system. Although this design measure significantly reduced the magnitude of pressure-wave surges, it was limited by the expansion of the period of pressure-wave oscillations. This study addressed a holistical exploration and comparison of the effectiveness of the in-series connections of multi-pipes design measure used to control water-hammer surges into an existing steel water distribution piping systems. The extended one-dimensional water-hammer model, including the Vitkovsky and Kelvin-Voigt formulations, was developed to describe the transient flow, together with the Method of Characteristics implemented for numerical computations. The comparison of the numerical solution with observed data, quoted in the literature, and the alternative numerical solution demonstrated the accuracy of the developed solver. The test case appraised the capability of a variety of in-series setups of steel and plastic main-pipes for a reservoir-pipe-valve – based hydraulic system. The high- and low-density polyethylene (HDPE and LDPE) plastic material types were considered in this investigation. Results showed that the hydraulic system setup built upon an (LDPE-steel-LDPE) provided a satisfactory tradeoff between the dampening of pressure-wave magnitude and the expansion of the period of pressure-wave oscillations