A deforming finite element mesh for use in moving one-dimensional boundary wave problems

✍ Scribed by C. D. Christian; G. N. Palmer

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 268 KB
• Volume: 25
• Category: Article
• ISSN: 0271-2091
• DOI: 10.1002/(sici)1097-0363(19970830)25:4<407::aid-fld556>3.0.co;2-6

✦ Synopsis

The ®nite element method is developed to solve the problem of wave run-up on a mild, plane slope. A novel approach to implementing a deforming mesh of one-dimensional, three-node, isoparametric elements is described and demonstrated. The discrete time interval (DTI), arbitrary Lagrangian±Eulerian (ALE) and space± time element (STE) methods are used to solve the unsteady one-dimensional shallow water wave equations. The boundary condition required is simply the seaward water surface elevation, and although the method has only been tested for monochromatic waves, it should be equally valid for any sea state which can be described as a water surface elevation as a function of time. All three solution methods are shown to given good results. Time histories of the terms of the governing equations are calculated and used to demonstrate how the ALE and STE methods account for mesh deformation. The model could be extended to two dimensions, which would have practical application to the run-up of obliquely incident waves.