This paper deals with the manners for generation of nonlinear shallow water waves In the laboratory. The displacements of the wavemaker plate for producing onoidal and solitary waves are derived based on the kinematic boundary condition. The experimental results show that well formed onoidal and solitary waves can he reproduced by means of these displacements. Finally, the applicability of the wave theories is discussed from the view point of the wave profile and horizontal water partical velocities.
It Is very Important to generate nonlinear shallow water waves In the laboratory and to measure water particle velocities Induced by waves for the Investigations of various phenomena on coastal engineering such as wave forces, littoral drifts and so on. It has been known experimentally (Goda.1967) that It is extremely difficult to generate shallow water waves of finite amplitude In a manner that a wavemaker oscillates sinusoidally. The authors of the present paper noted that as a ratio of wave height to water depth is greater than 0.45.the long wave produced by the sinusoidally moving wavemaker could simply propogate In a short distance and break quickly. The breaking may be due to the reason that the velocity of the wavemaker plate in simple harmonic motion is not consistent With the water particle velocity of the long wave near the wavemaker plate. Therefore a correct displacement of the wavemaker plate IS necessary to generate shallow water waves In the wave tank. Secondly the experimental procedure is described and the experimental results are compared with the available wave theories such as Stokes wave theories, onoidal wave theories, the stream function theory, and solitary wave theories.
Consider the wave generation process In a shallow water tank. The wave Is generated by a wavemaker and propogates along the tank.