Articles | Volume 16, issue 11
https://doi.org/10.5194/gmd-16-3291-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-16-3291-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
13 Jun 2023
Development and technical paper |
| 13 Jun 2023
| 13 Jun 2023
An improved subgrid channel model with upwind-form artificial diffusion for river hydrodynamics and floodplain inundation simulation
School of Geographical Sciences, University of Bristol, Bristol, BS8 1QU, UK
Paul Bates
School of Geographical Sciences, University of Bristol, Bristol, BS8 1QU, UK
Jeffrey Neal
School of Geographical Sciences, University of Bristol, Bristol, BS8 1QU, UK
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Short summary
A novel subgrid channel (SGC) model is developed for river–floodplain modelling, allowing utilization of subgrid-scale bathymetric information while performing computations on relatively coarse grids. By including adaptive artificial diffusion, potential numerical instability, which the original SGC solver had, in low-friction regions such as urban areas is addressed. Evaluation of the new SGC model through structured tests confirmed that the accuracy and stability have improved.
A novel subgrid channel (SGC) model is developed for river–floodplain modelling, allowing...
