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Title: Evaluating the Impact of Lossy Compression on a Direct Numerical Simulation of a Mach 2.5 Turbulent Boundary Layer
Lossy compression techniques are ubiquitous in many fields including imagery and video; however, the incursion of such lossy compression techniques in the computational fluid dynamics community has not advanced to the same extent in decades. In this work, the lossy compression of high-fidelity direct numerical simulation (DNS) is evaluated to assess the impact on various parameters of engineering interest. A Mach 2.5, spatially developing turbulent boundary layer (SDTBL) at a moderately high Reynolds number has been selected as the subject of the study. The ZFP compression scheme was chosen as the core driving algorithm for this study as it was carefully crafted for scientific, floating point data. The resilience of spectral quantities as well as two-point correlations is highlighted. Notwithstanding, we also noted that point-wise values calculated in the physical domain were prone to quantization errors at high compression ratios. Further, we have also presented the impact on higher order statistics. In summary, we have demonstrated that high fidelity results are within reach while achieving 1.45x to 9.82x reductions in required storage over single precision, IEEE 754-compliant data values.  more » « less
Award ID(s):
2314303 1847241
PAR ID:
10415197
Author(s) / Creator(s):
;
Date Published:
Journal Name:
AIAA SciTech Forum (AIAA 3773400) 23 - 27 January, 2023
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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