Hostname: page-component-cd4964975-ppllx Total loading time: 0 Render date: 2023-03-29T16:53:26.222Z Has data issue: true Feature Flags: { "useRatesEcommerce": false } hasContentIssue true

Experimental investigation and numerical modelling of steep forced water waves

Published online by Cambridge University Press:  19 August 2003

Department of Mechanical Engineering, Building 101E, Technical University of Denmark, DK-2800 Lyngby, Denmark Present address: School of Mathematics, University of Bristol, Bristol BS8 1TW, UK.
Dipartimento di Ingegneria Ambientale, University of Genova, Via Montallegro 1, 16145 Genova, Italy
School of Mathematics, University of Bristol, Bristol BS8 1TW, UK
Laboratoire de Mécanique de Lille, Université des Sciences et Technologies de Lille, Cité Scientifique, 59655 Villeneuve d'Ascq Cedex, France


Steep forced water waves generated by moving a rectangular tank are investigated both experimentally and numerically. Our main focus is on energetic events generated by two different types of external forcing. Horizontal motions are arranged to give wave impact on the sidewall. Steep standing waves forced by vertical acceleration can result in spectacular breaking modes similar to, and more energetic than, those reported by Jiang, Perlin & Schultz (1998, hereinafter J98). Among them we find thin sheets derived from sharp-crested waves, (‘mode A’ of J98) and the ‘flat-topped’ crest or ‘table-top’ breaker (‘mode B’ of J98). We report here on experimental observations of ‘table-top’ breakers showing remarkably long periods of free fall motion. Previously such breakers have only been observed in numerical computations. Both types of breakers often thin as they fall to give thin vertical sheets of water whose downward motion ends in either a small depression and a continuing smooth surface, or air entrainment to appreciable depths. Experimental results are compared graphically with numerical results of two theoretical models. One is an extended set of Boussinesq equations following Wei et al. (1995), which are successful up to wave slopes of O(1). The other numerical comparison is with a fully nonlinear irrotational flow solver (Dold 1992) which can follow the waves to breaking.

© 2003 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)