Influence of Wave Shape on the Impact of Shallow-Water Waves on Vertical Walls

A numerical study of the impact of shallow-water waves on vertical walls is presented. The air-liquid flow was simulated using a code for incompressible viscous flow, based on a local level set algorithm and a second-order approximate projection method. The level set transport and reinitialization equations were solved in a narrow band around the interface using an adaptive refined grid. The wave is assumed to be generated by a plunger which is accelerated in an open channel containing water. An arbitrary Lagrangian-Eulerian method was used to take into account the relative movement between the plunger and the end wall of the channel. The evolution of the free surface was visualized using a laser light sheet and a high-speed camera, with a sampling frequency of 1000 Hz. Several simulations were carried out to investigate the influence of the shape of the wave approaching the wall on the relevant quantities associated with the impact. The wave shape just before the impact was changed varying the total length of the channel. The results are compared with experimental results and with results obtained by other authors.

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Manoeuvring Study of a Container Ship in Shallow Water Waves

Volume 11B: Honoring Symposium for Professor Carlos Guedes Soares on Marine Technology and Ocean Engineering ◽

10.1115/omae2018-78294 ◽

2018 ◽

Author(s):

Manases Tello Ruiz ◽

Marc Mansuy ◽

Guillaume Delefortrie ◽

Marc Vantorre

Keyword(s):

Shallow Water ◽

Water Waves ◽

Numerical Study ◽

Scale Model ◽

Wave Forces ◽

Shallow Water Waves ◽

The North ◽

Captive Model Tests ◽

Calm Water ◽

Large Container

When approaching or leaving a port a ship often needs to perform manoeuvres in the presence of waves. At the same time the water depth is still limited for deep drafted vessels. For manoeuvring simulation purposes this requires a manoeuvring model which includes phenomena such as short crested waves and squat effects. The present paper addresses the manoeuvring problem in shallow water waves numerically and experimentally. The numerical study is conducted by means of potential theory, incorporating first and second order exciting wave forces, and their superposition to the calm water manoeuvring models. The applicability of such an approach is also investigated. The experimental work has been conducted at Flanders Hydraulics Research (in cooperation with Ghent University) with a scale model of an ultra large container vessel. Captive model tests comprise harmonic yaw tests and steady straight line tests with and without waves, at different forward speeds, wave frequencies and amplitudes, in head and following waves. Waves are chosen to represent conditions commonly met by ships in the Belgian coastal zone of the North Sea.

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Numerical study of nonlinear shallow water waves produced by a submerged moving disturbance in viscous flow

Physics of Fluids ◽

10.1063/1.868822 ◽

1996 ◽

Vol 8 (1) ◽

pp. 147-155 ◽

Cited By ~ 9

Author(s):

Daohua Zhang ◽

Allen T. Chwang

Keyword(s):

Viscous Flow ◽

Shallow Water ◽

Water Waves ◽

Numerical Study ◽

Shallow Water Waves

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Numerical study on Fermi–Pasta–Ulam–Tsingou problem for 1D shallow-water waves

Wave Motion ◽

10.1016/j.wavemoti.2013.07.002 ◽

2014 ◽

Vol 51 (1) ◽

pp. 157-167 ◽

Cited By ~ 1

Author(s):

Jinhai Zheng ◽

Gang Wang ◽

Guohai Dong ◽

Xiaozhou Ma ◽

Yuxiang Ma

Keyword(s):

Shallow Water ◽

Water Waves ◽

Numerical Study ◽

Shallow Water Waves

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Direct Numerical Simulation of the First Stages of a Plunging Breaker Using a Level Set Method

Volume 1: Symposia, Parts A, B and C ◽

10.1115/fedsm2009-78362 ◽

2009 ◽

Author(s):

Pablo Go´mez ◽

Claudio Zanzi ◽

Julia´n Palacios ◽

Joaqui´n Lo´pez ◽

Julio Herna´ndez

Keyword(s):

Level Set Method ◽

Level Set ◽

Stokes Equations ◽

Numerical Study ◽

Local Level ◽

Wave Crest ◽

Small Scale ◽

Breaking Wave ◽

Mass Force ◽

The Impact

A numerical study of wave breaking in shallow water is presented. The jet formed at the wave crest and the subsequent splash-up phenomenon resulting from the impact of the jet on the liquid surface are analyzed. The wave is assumed to be generated by an accelerated piston in an open channel containing liquid. The two-dimensional, incompressible, unsteady Navier-Stokes equations are solved using a local level set method to treat the interface evolution [Go´mez et al., Int. J. Numer. Meth. Engng, 63, pp. 1478–1512, 2005], which permits to analyze the combined air-liquid flow. Viscous and capillary effects are retained. The level set transport and reinitialization equations are solved in a narrow band around the interface using an adaptive refined grid. Two different approaches are considered to take into account the relative movement between the piston and the end wall of the channel. The first one uses a fixed grid and introduces a mass force per unit mass equal to the piston acceleration, and the second one is based on using a moving grid, which is compressed as the piston moves forward, and an arbitrary Lagrangian-Eulerian method. The numerical results obtained for the evolution of the wave shape during the breaking process, particularly the evolution of the plunging jet, the air cavity and the complex flow resulting from the impact of the plunging jet, are compared with experimental visualization results obtained for a small-scale breaking wave, for which the breaking process is strongly influenced by surface tension. A good degree of agreement was observed between both types of results during the first stages of the breaking process.

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