Water Hammer Mitigation by Air Vessel and Bypass Forward Configuration

In many industrial applications, liquid is transported by pipelines under high pressure conditions. Thus, any considerable change of fluid velocity will induce destructive pressure waves which may threaten the safety of the hydraulic system. Therefore, finding an effective and appropriate transient control technique is the objective of most related studies. In this paper, the effect of air vessel and HDPE (high density polyethylene) forward configuration techniques on the induced pressure waves were investigated experimentally and numerically. As the transient conditions are triggered owing to the sudden pump trip, each control technique was individually and jointly implemented. Regardless of control devices, the effect of changing the control operational scenario on the generated pressure waves were further investigated. Consequently, the experiments revealed that air vessel and HDPE forward configuration techniques have considerable damping effect to attenuate the water hammer, but the combination of both techniques has higher damping efficiency. Equally important, the changing of the operational scenario affects the severity of the induced surges. As well, the performance of air vessel and the HDPE forward configuration was affected by changing the operational scenario. Finally, the experimental and the numerical results are reasonably converged.