Halldor Arnason, Catherine Petroff, and Harry Yeh
In a laboratory wave tank, bores were generated by dam-break: by lifting a gate that initially separated quiescent shallow water from a volume of impounded water. The study was motivated by the problem of tsunami-structure interaction and sought to further the understanding of interactions between the bore-like flow of a broken tsunami wave and structures of different cross sections. Experiments were designed to observe the structure°«s effect on the bore as well as the bore°«s effect on the structure. This comprehensive study used highly repeatable experiments to measure water-surface variations, velocity flow fields, and forces exerted by bores on vertically erected columns. The temporal and spatial variations of the water-surface elevations were quantified with a Laser-Induced Fluorescence (LIF) technique; velocity flow fields were recorded with a combination of Laser Doppler Velocimeter (LDV) and Digital Particle Image Velocimetry (DPIV); forces on the columns were measured with a miniature load-cell transducer. The laboratory data obtained in the study are available for validating numerical models that predict forces on structures in unsteady flows.
Keywords: tsunamis, bore, wake, turbulence, force, method of characteristics, cylinder, column