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Hydrodynamics of Local Tsunami Effects - Numerical and Scale Model Results Based on Laboratory Experiments at the University of Washington and Numerical Simulation at Southern Methodist University (National Science Foundation Grant CMS-9614120) 1957 Aleutian Tsunami Laie Point,
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Hydrodynamics of Local Tsunami Effects - Numerical and Scale Model Results Based on Laboratory Experiments at the University of Washington and Numerical Simulation at Southern Methodist University (National Science Foundation Grant CMS-9614120)
1957 Aleutian Tsunami Laie Point, Oahu, Hawaii Photo Credit: Henry Helbush. Source: NGDC
Photos of incoming tsunami at La Manzanillo, Mexico on October 9, 1995 (Mw = 8.0) Courtesy of J. Borrerro, USC
Ishikawa River on Hokkaido Island Pedestrians on seawall 1983 Sea of Japan Tsunami, (Video footage courtesy of NHK)
Hilo Harbor Puumaile Tuberculosis Hospital 1946 Aleutian tsunami in Hilo, Hawaii. 96 people died, $26 million damage. (Photos courtesy of NGDC) Kamehameha Ave., Hilo
Isla Chiloe, Chile about 200 mortalities Hilo, Hawaii 61 mortalities 1960, Chilean tsunami (Mw = 8.6) (photos courtesy of NGDC)
Pancer, East Java. The tsunami of June 3, 1994 took the lives of 126 people and destroyed 671 structures.
Tsunami protection structures on the East Coast of Japan. (Photos courtesy of A. Moore)
Views of Laboratory Instruments Pneumatic Gate Cylindrical Obstacle Force Cell in Cylinder
Obstacle Gate Water Walls Side View 30 40 50 12 58 24 Top View 12 25 Schematic of Experiment (all dimensions in cm)
15 16 18 17 Laser Light Sheet Images of Water Surface: Frames 15-18
20 19 21 22 Laser Light Sheet Images of Water Surface: Frames 19-22
Surface Profile Acquisition: Raw Data from Frame 19
Surface Profile Acquisition: Processed Data from Frame 19
Comparison: Force Data from 4 Repetitions of Same Experiment Run 1 Run 2 Run 3 Run 4
Comparison: Lab Force Data with Three-Dimensional Surface Marker and Micro Cell (3DSMMC) Technique Force (N) Time (s)
Comparison: Lab Velocity Data with Three-Dimensional Surface Marker and Micro Cell (3DSMMC) Technique 1 Horizontal Velocity (m/s) 0 Time (s)
• Linear Momentum: F = mvx = (Avx)vx Drag Force: F = 1/2CDAvx2, CD = 2
Some Conclusions: 1. Laboratory and numerical results confirm that the maximum force occurs when the area behind the bore head begins to impact the obstacle. 2. The 3DSMMC horizontal forces on the square obstacle and of the velocity field model gives an accurate prediction of the around the obstacle during the progression of the bore. 3. For the square obstacle facing into the flow, using the measured maximum velocity in the bore and either conservation of linear momentum or a drag force calculation yields a good first order estimate of the maximum force.
Hydrodynamics of Local Tsunami Effects - Numerical and Scale Model Results H. Yeh, C. Petroff and H. Arnason Department of Civil & Environmental EngineeringUniversity of Washington, USA R. Bidoae and P. Raad Department of Mechanical Engineering Southern Methodist University, USA