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DOE OSTI · 1900503

A second-order distributed memory parallel fast sweeping method for the Eikonal equation

Tro, Sara Kauffman·Mera Evans, Tyco Brahe·Aslam, Tariq Dennis·Lozano Sanchez, Jose Eduardo·Culp, David Benjamin
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Abstract

The Eikonal equation is used to calculate wave propagation and distance fields, and due to its complexity requires numerical treatment for its solution. In this work, we present a second-order distributed memory parallel fast sweeping method. The second-order solution switches on a two-point stencil when two upwind points are available, and reverts to first-order otherwise. In all examples, the second-order method improves the solution over the first-order, allowing for significant savings in memory while achieving the same accuracy. Parallelization over distributed memory saw good weak scaling with optimal convergence. The computational time for second-order was approximately 2.5 times slower than first-order, where the largest amount of mesh points ran on 144 cores (512 GB) was ≈20 billion. The savings in memory from the second-order method combined with the distributed memory algorithm result in the ability to solve problems much larger than are possible with the serial first-order method.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSEikonal equationFast sweeping methodParallelizationSecond-order

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Tro, Sara Kauffman, Mera Evans, Tyco Brahe, Aslam, Tariq Dennis, Lozano Sanchez, Jose Eduardo, Culp, David Benjamin. 2022-11-17. A second-order distributed memory parallel fast sweeping method for the Eikonal equation. https://doi.org/10.1016/j.jcp.2022.111785

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