Assessment of Steady and Unsteady Friction Models in the Draining Processes of Hydraulic Installations

The study of draining processes without admitting air has been conducted using only steady friction formulations in the implementation governing equations. However, this hydraulic event involves transitions from laminar to turbulent flow, and vice versa, because changes water velocity. In sense, research improves current mathematical model considering unsteady models. An experimental facility composed by a 4.36 m long methacrylate pipe was configured, measurements pocket pressure oscillations were recorded. performed Comparisons between measured computed patterns indicated that models slightly improve results compared