Author(s): Schoberl Friedrich; Reindl Robert
Linked Author(s):
Keywords: Bottom outlet; Flow airation; 2-phase flow; Pressure pulsations; Scale effects
Abstract: The bottom outlet tunnel of the Gepatsch dam in Austria is combined with the shaft spillway. In case of the activated flood release, a pulsating 2-phase flow of water and air can emerge, causing additional high dynamic loads on the outlet gate. Physical scale models combined with theoretical investigations served to check the responsible flow conditions and to prove measures for preventing the initiation of such phenomena. For the prototype assessment of critical conditions, scale-effects had to be taken into account. Design studies showed, that the provision of an additional gate in the outlet tunnel or in the ventilation shaft would be most appropriate solution. Each of these measures is able to deactivate the undesirable emission of the water-air mixture and to successfully attenuate the level of pulsations.
Year: 2007