Unsteady Flow Effect on Pipeline Networks: Numerical Study for the Effect of Water Hammer on Pipeline Networks

The protection of the irrigation pipeline networks against Water Hammer -as a result of pump power failure- is of great importance. In this study, an improved design for irrigation pipeline networks is investigated. Basic partial differential equations based on one-dimensional homogenous flow model are formulated and solved by the method of characteristics. The differential equations of momentum and continuity are developed for solving transient problem. For transient condition caused by pump failure, four different scenarios were considered to study the impact of column separation of the pipelines system. These scenarios are the steady state condition, transient condition without protection, transient condition with air vessel as a protection and transient condition with air vessel and two surge towers as a protection. Also, the impact of changing diameter and wall thickness of pipes, changing material type and polar moment of inertia of the pump on the magnitude of the maximum pressure heads and column separation were included in the study. The Water Hammer Software "Wanda V3.30" was applied and the results were graphically presented for different relationships.