The ExaHyPE engine supports simulation of systems of hyperbolic PDEs, as stemming from conservation laws. A concrete model for seismic wave propagation problems is being developed within the ExaHyPE project. The model is based on high-order Discontinuous Galerkin (DG) discretization, local time-stepping and works on octree-structured Cartesian meshes. The activities in this CoE will focus on setting up concrete services based on the ExaHyPE engine and seismic models.
High-performance package for waveform modelling and inversion with applications ranging from laboratory ultrasound studies to planetary-scale seismology. Solves dynamic (visco-)acoustic and elastic wave propagation problems on fully unstructured hypercubic and simplicial meshes in 2 and 3 dimensions using a spectral-element approach.
SeisSol solves seismic wave propagation (elastic, viscoelastic) and dynamic rupture problems on heterogeneous 3D models. SeisSol uses high-order DG discretization and local time-stepping on unstructured adaptive tetrahedral meshes. Scalable performance at Petascale has been demonstrated up to several thousand nodes (on several supercompers, e.g., Cori, SuperMUC, Hazel Hen, Shaheen, etc.). Earlier work considered offload schemes that scaled to 8000 nodes on the Tianhe-2 supercomputer (Xeon Phi, Knights Corner).
SPECFEM3D solves linear seismic wave propagation (elastic, viscoelastic, poroelastic, fluid-solid) and dynamic rupture problems in heterogeneous 3D models. SPECFEM3D also implements imaging and FWI for such complex models based on an L-BFGS (Broyden-Fletcher-Goldfarb-Shanno) algorithm. Based on the high-order spectral-element (CG) discretization for unstructured hexahedral meshes. Scalable performance at Petascale (runs on the largest machines worldwide: Titan and Summit at Oak Ridge, Piz Daint, CURIE, K computer, etc.)
PARODY_PDAF simulates incompressible MHD in a spherical cavity. In addition to the Navier-Stokes equations with an optional Coriolis force, it can also time-step the coupled induction equation for MHD (with imposed magnetic field or in a dynamo regime), as well as the temperature (and concentration) equation in the Boussinesq framework. It offers the possibility to perform ensemble assimilation experiments, being connected with the parallel data assimilation framework (PDAF) library. Based on a semi-spectral approach combining finite differences in radius and spherical harmonics, semi-implicit second-order time scheme.
XSHELLS simulates incompressible fluids in a spherical cavity. In addition to the Navier-Stokes equation with an optional Coriolis force, it can also time-step the coupled induction equation for MHD (with imposed magnetic field or in a dynamo regime), as well as the temperature (and concentration) equation in the Boussinesq framework. Based also on a semi-spectral approach combining finite differences in radius and spherical harmonics, semi-implicit second-order time scheme.
Multiphase fluid dynamic model conceived for compressible mixtures composed of gaseous components and solid particle phases. All phases are treated using the Eulerian approach, identifying a solid phase as a class of particles with similar dynamical properties. The physical model is based on the equilibrium-Eulerian approach while the gas-particle momentum non-equilibrium is approximated by a prognostic equation accurate to the first order. As a result, the model reduces to a single (vector) momentum equation and one energy equation for the mixture (corrected to account for non-equilibrium terms and mixture density fluctuations) and one continuity equation for each gaseous or solid component. In addition, Lagrangian particles are injected in the domain and “two/four-way” coupled with the Eulerian field. Discretization is based on the Finite-Volume method on an unstructured grid. The numerical solution adopts a segregated semi-implicit approach.
FALL3D is a Eulerian model for the atmospheric transport and ground deposition of volcanic tephra (ash). FALL3D solves a set of advection-diffusion-sedimentation (ADS) equations on a structured terrain-following grid using a second-order Finite Differences (FD) explicit scheme.
T-HySEA solves the 2D shallow water equations on hydrostatic and dispersive versions. T-HySEA is based on a high-order Finite Volume (FV) discretization (hydrostatic) with Finite Differences (FD) for the dispersive version on two-way structured nested meshes in spherical coordinates. Initial conditions from the Okada model or initial deformation, synchronous and asynchronous multi-Okada, rectangular and triangular faults.
L-HySEA solves the 2D shallow water/Savage-Hutter coupled equations, hydrostatic fully coupled and dispersive weakly coupled versions. L-HySEA is based on high-order FV discretization (hydrostatic) with FD for dispersive model, structured meshes in Cartesian coordinates.