SEAMLESS-WAVE
SEAMLESS-WAVE is a developing “SoftwarE infrAstructure for Multi-purpose fLood modElling at variouS scaleS” based on "WAVElets" and their versatile properties. The vision behind SEAMLESS-WAVE is to produce an intelligent and holistic modelling framework, which can drastically reduce iterations in building and testing for an optimal model setting, and in controlling the propagation of model-error due to scaling effects and of uncertainty due statistical inputs.
Using the non-uniform ACC solver
The non-uniform ACC solver is distributed as a new solver in the LISFLOOD-FP ecosystem and follows the same standard usage with a few updates to input/output components.
Setting up the simulations for using the new non-uniform ACC solver follows the same conventions of LISFLOOD-FP as described in section “Input files and their format”, with a few updates to the .par file:
- The non-uniform ACC solver is selected by including item
acc_nugrid. - The error threshold, $\varepsilon$, is selected by including item
epsilon, followed by a float number refering to the value of $\varepsilon$. - The maximum refinement level, L, is selected by including the item
L, followed by an integer refering to the value of L. - The 2D model outputs are generated in two forms:
- Multiresolution grid as
.vtkfile format (see section “Non-uniform grid output files (-xxxx.vtk)” for visualising.vtkfiles). - Standard uniform grid raster files (Recall section “Water depth or free-surface elevation output files (-xxxx.wd, -xxxx.elev)”).
By default both of these files are generated at the intervals specified by item
saveint. However, the generation of the.vtkfiles can be suppressed (to save disk space) by including the itemvtkoff. - Multiresolution grid as
These modifications to the .par files are summarised in the table below.
Item name input |
Description | Solver |
|---|---|---|
| acc_nugrid | Selects the non-uniofrm ACC solver | non-uniform ACC |
| cuda | Runs the selected solver on GPU | All |
| epsilon | The choice of error threshold, $\varepsilon$ | non-uniform ACC |
| L | The maximum refinement levels, L | non-uniform ACC |
| vtkoff | Suppress production of 2D multiresolution map files (*.vtk) |
non-uniform ACC |
The technical background of how the ACC solver is adapted on the non-uniform grid generated by the multiwavets Galerkin projection of the DEM, and parallised on the GPU can be found in the preprint, which provides a demonstration of the solver performance for five real-world fluvial/pluvial case studies.
These flooding case studies include three catchment-scale scenarios and two urban-scale scenarios that are summarised in table below.
| Test Case | Source | Type | Number of elements (thousands) | L | R (m) | Simulation time (hr) |
|---|---|---|---|---|---|---|
| Lower triangle catchment | Özgen-Xian et al., 2020 | Pluvial | 149, 594, 3700 | 10, 11, 12 | 10, 5, 2 | 72 |
| Upper Lee Catchment | Xia and Liang, 2018 | Pluvial | 2712 | 12 | 20 | 120 |
| Eden catchment | Xia et al., 2019 | Fluvial | 6276 | 13 | 20 | 132 |
| Glasgow urban area | Néelz and Pender, 2013 | Pluvial | 95 | 9 | 2 | 5 |
| Cockermouth urban area | Muthusamy et al., 2021 | Fluvial | 2160 | 11 | 1 | 144 |
Step by step instructions on how to download and install the LISFLOOD-FP code, and reproduce the simulations for representative case studies can be found in the following videos links.