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Statistical Analysis of Solutions from the Sixth AIAA Computational Fluid Dynamics Drag Prediction Workshop
Joseph M Derlaga1, Joseph H Morrison1
1NASA Langley Research Center, Hampton, Virginia, 23681.
Journal of Aircraft
|January 22, 2021
Summary
This study analyzed computational fluid dynamics (CFD) code results from a drag prediction workshop. A common grid sequence significantly reduces solution variations among different CFD codes.
Area of Science:
- Computational Fluid Dynamics (CFD)
- Aerodynamics
- Statistical Analysis
Background:
- Reynolds-averaged Navier-Stokes (RANS) codes are crucial for aerodynamic simulations.
- Previous Drag Prediction Workshops (DPWs) highlighted the need for standardized analysis.
- The Common Research Model (CRM) wing-body has been a benchmark in prior studies.
Purpose of the Study:
- To statistically analyze results from an N-version test of CFD codes.
- To compare grid convergence study outcomes with previous workshops.
- To assess the impact of common grid sequences on solution variability.
Main Methods:
- Utilized a graphical framework for statistical analysis.
- Analyzed data from the 6th AIAA CFD Drag Prediction Workshop (June 2016).
- Included results from international code developers and users employing various grid sequences and turbulence models.
Main Results:
- Reinforced the importance of a common grid sequence in reducing solution variation.
- Demonstrated less scatter in predicted drag increments compared to absolute drag values.
- Highlighted the influence of grid strategy and turbulence models on CFD code predictions.
Conclusions:
- Common grid sequences are vital for decreasing solution variation in CFD simulations.
- Analyzing drag increments offers a more consistent comparison between different CFD codes.
- Continued statistical analysis across workshops refines understanding of CFD code performance.
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