Book Description

The kinematics of surface gravity waves produced in water 2.5 feet deep in a basin 90 feet square by a sudden, localized disturbance was studied through measurements of height and period. The waves were generated by the quick withdrawal or immersion, or combinations of these actions, of a 14-foot-diameter half-paraboloid plunger located near the mid-point of one wall of the basin. Smaller plungers of diverse shapes were also used. Measurements were made both in the constant-depth portion of the basin and over a beach with a uniform slope of 1:13.6, which was directly opposite the plunger. At the shoreline about 80 feet from the plunger, waves produced by a sudden withdrawal, for example, were 3 inches high, with a maximum period of 3 seconds. The waves compare adequately with those predicted by the theory of Kranzer and Keller, although they were 40% smaller and 20% shorter. By extrapolation, it was found that waves were produced which adequately simulated those from the actual underwater detonation of a high-energy explosive (5 tons TNT) and a nuclear device (20 kt equivalent). It is concluded that with proper scaling the plunger can be used to simulate waves from such causes. (Author).