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arXiv · 1902.00088

An open and parallel multiresolution framework using block-based adaptive grids

Mario Sroka·Thomas Engels·Philipp Krah·Sophie Mutzel·Kai Schneider·Julius Reiss
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Abstract

A numerical approach for solving evolutionary partial differential equations in two and three space dimensions on block-based adaptive grids is presented. The numerical discretization is based on high-order, central finite-differences and explicit time integration. Grid refinement and coarsening are triggered by multiresolution analysis, i.e. thresholding of wavelet coefficients, which allow controlling the precision of the adaptive approximation of the solution with respect to uniform grid computations. The implementation of the scheme is fully parallel using MPI with a hybrid data structure. Load balancing relies on space filling curves techniques. Validation tests for 2D advection equations allow to assess the precision and performance of the developed code. Computations of the compressible Navier-Stokes equations for a temporally developing 2D mixing layer illustrate the properties of the code for nonlinear multi-scale problems. The code is open source.

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BibTeXRIS

Mario Sroka, Thomas Engels, Philipp Krah, Sophie Mutzel, Kai Schneider, Julius Reiss. 2019-01-29. An open and parallel multiresolution framework using block-based adaptive grids. https://doi.org/10.1007/978-3-319-98177-2_19

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