Author(s): Gerald Muller

Linked Author(s): Gerald Muller

Keywords: Vertical jet; Vertical uprush; Sudden gate closure; Tsunami impact

Abstract: During the emergency closure of a sluice gate at hydropower station inlets, or at the collision of a tsunami bore with a vertical wall, a sudden and complete deceleration of a moving water mass can occur. Experiments were conducted to model this sudden deceleration of a supercritical flow. It was observed that during such an event, a fast vertical jet can develop, with a vertical velocity of three times the horizontal velocity. A linearised theory was developed to describe the jet generation and characteristics. The theory employs the connected horizontal de- and vertical acceleration of a fluid body in contact with a vertical wall, governed by the requirement for conservation of energy and mass. The theory showed good agreement with the measurements, indicating its validity. With the theory, the additional pressures generated by the collision can be estimated.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0269-cd

Year: 2023