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NASA NTRS · 20160006398

Parallel Adjective High-Order CFD Simulations Characterizing SOFIA Cavity Acoustics

Barad, Michael F.·Brehm, Christoph·Kiris, Cetin C.·Biswas, Rupak
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Abstract

This paper presents large-scale MPI-parallel computational uid dynamics simulations for the Stratospheric Observatory for Infrared Astronomy (SOFIA). SOFIA is an airborne, 2.5-meter infrared telescope mounted in an open cavity in the aft fuselage of a Boeing 747SP. These simulations focus on how the unsteady ow eld inside and over the cavity interferes with the optical path and mounting structure of the telescope. A temporally fourth-order accurate Runge-Kutta, and spatially fth-order accurate WENO- 5Z scheme was used to perform implicit large eddy simulations. An immersed boundary method provides automated gridding for complex geometries and natural coupling to a block-structured Cartesian adaptive mesh re nement framework. Strong scaling studies using NASA's Pleiades supercomputer with up to 32k CPU cores and 4 billion compu- tational cells shows excellent scaling. Dynamic load balancing based on execution time on individual AMR blocks addresses irregular numerical cost associated with blocks con- taining boundaries. Limits to scaling beyond 32k cores are identi ed, and targeted code optimizations are discussed.

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Barad, Michael F., Brehm, Christoph, Kiris, Cetin C., Biswas, Rupak. 2016-05-16. Parallel Adjective High-Order CFD Simulations Characterizing SOFIA Cavity Acoustics. https://ntrs.nasa.gov/citations/20160006398

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