(Multi)wavelet-based Godunov-type simulators of flood inundation: Static versus dynamic adaptivity

Real-world flood simulators often use first-order finite volume (FV1) solvers of the shallow water equations with efficiency enhancements exploiting parallelisation on Graphical Processing Units (GPUs) and static adaptivity fixed grids. A second-order discontinuous Galerkin (DG2) solver greatly increases accuracy in predictions uniform grids, where it is comparatively costly to run, but its practical utility as an alternative for simulations using not yet assessed. This also case dynamic multiresolution analysis (MRA) Haar wavelet (HW) scaling FV1 piecewise-constant solutions (HWFV1) smoother Multiwavelets (MWs) that scales DG2 piecewise-planar (MWDG2) adapt resolution their grids over time. Therefore, MWDG2 HWFV1 newly explored real-world simulations, find out when they yield better than adaptivity. new GPU implementation proposed include assess how far renders runtime practically feasible. Dynamic are assessed three tests involving slow, gradual rapid flows analyses predictive computational costs reference grid at finest digital elevation model (DEM). Findings suggest favouring long-duration slowly gradually propagating floods simulate events driven by rapidly flows. On GPU, faster DG2, leading a higher speedup ratio reduction elements initial, grid.