Preliminary numerical investigation of flows under high head gates

Vertical leaf gates are widely used in bottom outlets for discharge control and emergency closure, mainly because they present several advantages as regards construction and maintenance aspects; however, some flow features have not been completely clarified. Both experimental and numerical approaches were adopted in the past to deal with such a complex issue. However, the hydraulic behaviour of differently shaped gates in variable operating conditions, as well as the effects of acting forces such as downpull, are still unclear. Several parameters, both relating to the geometrical features and to operating conditions, should be considered together and contribute to conditioning the design and the operation of the system. This paper summarizes the initial results of research carried out jointly by the research teams of Politecnico di Bari and the manufacturer, ATB Riva Calzoni. An experimental plant is currently being designed, and preliminary CFD tests were performed mainly to define the main characteristics of the jets flowing under the device.