Long Wave Flow Interaction with a Single Square Structure on a Sloping Beach
AbstractIn the context of dam breaks, tsunami, and flash floods, it is paramount to quantify the time-history of forces by the rapidly transient flow to vertical structures and the characteristics of the induced flow patterns. To resemble on-land tsunami-induced flow, a free-surface-piercing structure is exposed to long leading depression waves in a tsunami flume where long waves run up and down a 1:40 smooth and impermeable sloping beach after its generation by a volume-driven wave maker. The structure and its surrounding were monitored with force transducers, pressure gauges and cameras. Preparatory steady-state experiments were accomplished to determine the drag force coefficient of the square cylinder at various water depths. The flow during wave run-up and draw-down acting on the structure resulted in distinct flow pattern which were characteristic for the type of flow-structure interaction. Besides bow wave propagating upstream, a standing or partially-standing wave was observed in front of the structure together with a wake formation downstream, while a von Kármán vortex street developed during the deceleration phase of the flow motion and during draw-down. Force measurements indicated a sudden increase in the stream-wise total force starting with the arrival of the flow front during initial run-up. Lateral velocities showed significant oscillations in correlation with the von Kármán vortex street development. A comparison of the total measured base force with the analytically-calculated share of the drag force revealed that forces were prevailingly drag-dominated. View Full-Text
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Bremm, G.C.; Goseberg, N.; Schlurmann, T.; Nistor, I. Long Wave Flow Interaction with a Single Square Structure on a Sloping Beach. J. Mar. Sci. Eng. 2015, 3, 821-844.
Bremm GC, Goseberg N, Schlurmann T, Nistor I. Long Wave Flow Interaction with a Single Square Structure on a Sloping Beach. Journal of Marine Science and Engineering. 2015; 3(3):821-844.Chicago/Turabian Style
Bremm, Gian C.; Goseberg, Nils; Schlurmann, Torsten; Nistor, Ioan. 2015. "Long Wave Flow Interaction with a Single Square Structure on a Sloping Beach." J. Mar. Sci. Eng. 3, no. 3: 821-844.