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Indexed by:期刊论文

Date of Publication:2014-10-01

Journal:OCEAN ENGINEERING

Included Journals:SCIE、EI、Scopus

Volume:89

Page Number:134-145

ISSN No.:0029-8018

Key Words:Non-hydrostatic model; Boundary-fitted coordinate; Nonlinear waves; Focusing waves; Freak wave

Abstract:This paper employs a three-dimensional (3D) non-hydrostatic model to simulate nonlinear focusing wave groups. The non-hydrostatic model utilizes an explicit projection method to solve the Navier-Stokes equations. To accurately simulate the steep free surface involved in focusing waves, the model is built upon a general boundary-fitted coordinate system. This grid system allows for a great adaptability of the vertical discretization and meanwhile maintains the boundary-fitted properties of better fitting the bed and free surface. The advantage of the general boundary-fitted model is first validated by two test cases of nonlinear waves, Including nonlinear standing waves and two-dimensional (2D) focusing freak wave. Then, the model is applied to simulate 20 focusing waves in deep and intermediate-water depths and 3D focusing waves in deep-water depth. By comparing with experimental data, the model results well reproduce the main characteristics of 2D deep-water focusing waves and 2D intermediate-water focusing waves as well as 3D deep-water focusing waves, demonstrating the model's capability to resolve 2D or 3D focusing wave groups. Furthermore, in the test of 20 intermediate-water focusing waves, the downstream shifting of the focusing position and time is also studied numerically, which is not presented in the experiments. (C) 2014 Elsevier Ltd. All rights reserved.