Showing papers on "Wave flume published in 1971"

Theory of explosion-generated water waves

Abstract: The present developments on explosion-generated waves are of direct application to all families of gravity waves. In particular, the development pertaining to nonlinear effects are of direct interest for better understanding of wind-generated water waves in shallow water. Also the development dealing with harbor resonance due to explosion waves is of direct interest to coastal engineers in order to better design harbors by minimizing the seiche effect.

U.S. Army coastal engineering research center

Abstract: Fig. 1. General view of sluice wave producer for generating waves in a large wave flume. The Twelfth Internat ional Conference on Coastal Engineering was held in Washington on September 13-18, 1970. The main topic of this conference [1] was devoted to problems of waves and their act ion on various structures, problems of hydraulic structures and individual aspects of their design, and to an analysis of coastal processes.

Forces due to waves on submerged structures

Abstract: Existing theories on wave forces on large submerged structures are reviewed. The equations regarding wave forces and moments on piles do not apply because inertial forces are predominant on a submerged structure which has a principle horizontal dimension equal or larger than the vertical dimension. Several models of simple geometric structures were installed in a two-dimensional laboratory wave tank. The magnitude of the vertical and horizontal loads on the structure by the wave action were determined experimentally. Values of coefficient of inertia were obtained for experimental data. Results of data wer plotted in dimensionless form to provide a correlation between ratios of wave length to water depth, wave height to wave length, and dimensionless force for a number of different shapes of structures. Measurements were also obtained for one of the models of forces due to irregular, wind-generated waves. Comparison between forces caused by regular waves and irregular waves was made. It is concluded that forces due to waves, particularly due to irregular waves generated by wind are highly variable, but results presented may be sufficient for preliminary designs.

A Further Investigation of the Distribution of Suspended Sediment Concentration Due to Standing Waves

Abstract: In the previous paper (Hattori, 1969), a theory for the distribution of suspended sediment concentration due to standing waves was obtained on the basis of the concept of delay distance of suspended sediment. Although the validity of the theory was confirmed by experiments, the physical properties of the delay distance were not fully investigated in the previous paper.In order to clarify the physical properties of the delay distance, further experiments have been made in a two-dimensional wave flume for standing waves.This paper discusses the relation between the delay distance and the wave characteristics using the experimental results. It is assumed that the diffusion coefficient of suspended sediment in the horizontal direction is equal to that in the vertical direction.The relation between the delay distance of suspended sediment and the characteristics of standing waves is obtained as follows; in which δx, is the delay distance of suspended sediment in the horizontal direction, ξ is the ampli...

The interaction between a vertical cylinder and regular waves

Abstract: The huge amount of offshore activities in recent years has increased the need of reliable data concerning the wave loading on vertical cylinders. A review is given of different methods, according to which the wave forces on a vertical circular cylinder can be calculated. Numerical results of these methods are compared with the results of model experiments. The wave diffraction around a cylindrical object was calculated with the potential theory and is compared with measurements of the wave amplitude.

Irregular Wave Action on Rubble-Mound Breakwaters

Abstract: An investigation was undertaken to compare the effect of regular and irregular waves on a rubble-mound breakwater model. During the experiments water depth, breakwater, and wave characteristics were kept constant; wave heights were varied. Experiments were conducted to determine the damage in terms of the displaced number of stones. It was concluded that the damage on a rubble-mound break-water is related to the energy of the attacking wave. Experiments revealed that relating the damage to the total energy is inaccurate. Consequently, this concept was replaced by a relationship between the damage and the effective energy, which is the part of the energy including the energy of waves higher than the design wave. Therefore, it was shown experimentally that the effective energy determines the different the different effects of regular and irregular wave action on the breakwater. It was shown that regular waves have the same effect as the irregular waves when the significant wave heights equal the heights of regular waves.