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arXiv · 1601.06984

Implementation of the compact interpolation within the octree based Lattice Boltzmann solver Musubi

Jiaxing Qi·Harald Klimach·Sabine Roller
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Abstract

A sparse octree based parallel implementation of the lattice Boltzmann method for non-uniform meshes is presented in this paper. To couple grids of different resolutions, a second order accurate compact interpolation is employed and further extended into three dimensions. This compact interpolation requires only four source elements from the adjacent level for both two- and three dimensions. Thus, it reduces the computational and communication overhead in parallel executions. Moreover, the implementation of a weight based domain decomposition algorithm and level-wise elements arrangement are explained in details. The second order convergence of both velocity and strain rate are validated numerically in the Taylor-Green vortex test case. Additionally, the laminar flow around a cylinder at Re = 20, 100 and around a sphere at Re = 100 is investigated. Good agreement between simulated results and those from literature is observed, which provides further evidence for the accuracy of our method.

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Jiaxing Qi, Harald Klimach, Sabine Roller. 2016-01-26. Implementation of the compact interpolation within the octree based Lattice Boltzmann solver Musubi. https://doi.org/10.1016/j.camwa.2016.06.025

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