Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers
This paper presents a new technique to compute open boundary conditions for fully-coupled hydro-morphodynamical numerical solvers based on the Non-Linear Shallow Water and the Exner equations. These conditions allow the generation of incident signals and the absorption of reflected ones, taking into...
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| Format: | Article |
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Elsevier
2015
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| Online Access: | https://eprints.nottingham.ac.uk/44700/ |
| _version_ | 1848796978495881216 |
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| author | Incelli, Giorgio Briganti, Riccardo Dodd, Nicholas |
| author_facet | Incelli, Giorgio Briganti, Riccardo Dodd, Nicholas |
| author_sort | Incelli, Giorgio |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | This paper presents a new technique to compute open boundary conditions for fully-coupled hydro-morphodynamical numerical solvers based on the Non-Linear Shallow Water and the Exner equations. These conditions allow the generation of incident signals and the absorption of reflected ones, taking into account the bed evolution at the boundary. They use the approximations for linear waves in shallow water and are based on the solution of the Riemann Equations.
The proposed technique is implemented in the fully-coupled hydro-morphodynamical numerical model of Briganti et al. (2012a).
Firstly, the generation and absorption of single monochromatic waves are studied to quantify the error after the reflected wave exited the domain. In all cases the error is always small, giving evidence of the effectiveness of the new seaward boundary conditions.
Furthermore, the propagation and reflection of a monochromatic wave train over a mobile bed are considered. Both flow evolution and bed change are not affected by spurious oscillations when long sequences of waves are tested. Additionally, a very low mobility bed is considered to simulate a ‘virtually fixed’ bed and new boundary condition results consistently converge to those for the hydrodynamic only case.
Finally, the reflection of a uniform bore over a mobile bed is studied. For this case the Rankine–Hugoniot conditions provide an analytical solution. It is apparent that the adopted linear approximations produce errors in the velocity estimates. Nevertheless, the conditions perform reasonably well even in this demanding non-linear case. |
| first_indexed | 2025-11-14T19:56:34Z |
| format | Article |
| id | nottingham-44700 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:56:34Z |
| publishDate | 2015 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-447002020-05-04T17:07:45Z https://eprints.nottingham.ac.uk/44700/ Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers Incelli, Giorgio Briganti, Riccardo Dodd, Nicholas This paper presents a new technique to compute open boundary conditions for fully-coupled hydro-morphodynamical numerical solvers based on the Non-Linear Shallow Water and the Exner equations. These conditions allow the generation of incident signals and the absorption of reflected ones, taking into account the bed evolution at the boundary. They use the approximations for linear waves in shallow water and are based on the solution of the Riemann Equations. The proposed technique is implemented in the fully-coupled hydro-morphodynamical numerical model of Briganti et al. (2012a). Firstly, the generation and absorption of single monochromatic waves are studied to quantify the error after the reflected wave exited the domain. In all cases the error is always small, giving evidence of the effectiveness of the new seaward boundary conditions. Furthermore, the propagation and reflection of a monochromatic wave train over a mobile bed are considered. Both flow evolution and bed change are not affected by spurious oscillations when long sequences of waves are tested. Additionally, a very low mobility bed is considered to simulate a ‘virtually fixed’ bed and new boundary condition results consistently converge to those for the hydrodynamic only case. Finally, the reflection of a uniform bore over a mobile bed is studied. For this case the Rankine–Hugoniot conditions provide an analytical solution. It is apparent that the adopted linear approximations produce errors in the velocity estimates. Nevertheless, the conditions perform reasonably well even in this demanding non-linear case. Elsevier 2015-05-31 Article PeerReviewed Incelli, Giorgio, Briganti, Riccardo and Dodd, Nicholas (2015) Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers. Coastal Engineering, 99 . pp. 96-108. ISSN 0378-3839 Fully-coupled morphodynamics Open boundary Absorbing-generating boundary conditions Non-Linear Shallow Water Equations Exner equation http://www.sciencedirect.com/science/article/pii/S0378383915000253?via%3Dihub doi:10.1016/j.coastaleng.2015.02.002 doi:10.1016/j.coastaleng.2015.02.002 |
| spellingShingle | Fully-coupled morphodynamics Open boundary Absorbing-generating boundary conditions Non-Linear Shallow Water Equations Exner equation Incelli, Giorgio Briganti, Riccardo Dodd, Nicholas Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title | Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title_full | Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title_fullStr | Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title_full_unstemmed | Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title_short | Absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| title_sort | absorbing–generating seaward boundary conditions for fully-coupled hydro-morphodynamical solvers |
| topic | Fully-coupled morphodynamics Open boundary Absorbing-generating boundary conditions Non-Linear Shallow Water Equations Exner equation |
| url | https://eprints.nottingham.ac.uk/44700/ https://eprints.nottingham.ac.uk/44700/ https://eprints.nottingham.ac.uk/44700/ |