neashton/ahmedml

AhmedML: High-Fidelity Computational Fluid Dynamics dataset for incompressible, low-speed bluff body aerodynamics

Contact:

Neil Ashton (NVIDIA) - [email protected]

website:

https://caemldatasets.org

Summary:

This dataset contains 500 different geometric variations of the Ahmed Car Body - a simplified car-like shape that exhibits many of the flow topologies that are present on bluff bodies such as road vehicles. The dataset contains a wide range of geometries that exhibit fundamental flow physics such as geometry and pressure-induced flow separation of flows as well as 3D vortical structures. Each variation of the Ahmed car body were run using a time-accurate hybrid Reynolds-Averaged Navier-Stokes (RANS) - Large-Eddy Simulation (LES) turbulence modelling approach using the open-source CFD code OpenFOAM. The dataset contains both surface boundary, 3D volume, geometry STL and forces/moments in open-source formats (.vtu,.vtp).

CFD Solver:

All cases were run using the open-source finite-volume code OpenFOAM v2212. Each case was run transiently for approximately 80 convective time units (CTU) on meshes of approximately 20M cells. Please see the paper for full details on the code and validation:

How to cite this dataset:

In order to cite the use of this dataset please cite the paper below which contains full details on the dataset. It can be found here: https://arxiv.org/abs/2407.20801

@article{ashton2024ahmed, title = {{AhmedML: High-Fidelity Computational Fluid Dynamics dataset for incompressible, low-speed bluff body aerodynamics}}, year = {2024}, journal = {arxiv.org}, author = {Ashton, Neil and Maddix, Danielle and Gundry, Samuel and Shabestari, Parisa} }

Files:

Each folder (e.g run_1,run_2...run_"i" etc) corresponds to a different geometry that contains the following files where "i" is the run number:

• ahmed_i.stl : geometry stl (~5mb):
• geo_parameters_1.csv (missing run 500): parameters that define the geometry
• boundary_i.vtp : Boundary VTP (~500mb)
• volume_i.vtu : Volume field VTU (~5GB)
• force_mom_i.csv : forces (Cd,Cl) time-averaged with constant reference area
• force_mom_varref_i.csv : forces (Cd,Cl) time-averaged with varying reference area
• slices : folder containing .vtp slices in x,y,z that contain flow-field variables
• images : (folder) that contains images of the following variables (CpT, UxMean) for slices of the domain in the X,Y & Z locations. In addition we provide:
• force_mom_all.csv : run, cd,cl for all runs in a single file
• force_mom_varref_all.csv : run, cd,cl for all runs in a single file with varying reference area
• geo_parameters_all.csv : all the geometry parameters for each run inside a single file
• ahmedml.slvs : SolveSpace input file to create the parametric geometries
• stl : folder containing stl files that were used as inputs to the OpenFOAM process
• openfoam-casesetup.tgz : complete OpenFOAM setup that can be used to extend or reproduce the dataset
• validation : folder containing full outputs from all four mesh levels that were used to validate the methodology

Acknowledgements

• OpenFOAM solver and workflow development by Neil Ashton (Amazon Web Services, now NVIDIA)
• Geometry parameterization by Samuel Gundry (Amazon Web Services) and Parisa Shabestari (Amazon Web Services)
• Guidance on dataset preparation for ML by Danielle Madix (Amazon Web Services)
• Simulation runs, HPC setup and dataset preparation by Neil Ashton (Amazon Web Services, now NVIDIA)

License

This dataset is provided under the CC BY SA 4.0 license, please see LICENSE.txt for full license text.

version history:

• 15/02/2025 - files uploaded to HuggingFace
• 12/11/2024 - added validation folder that contains the full output from all four mesh levels that were used to validate the methodology used.
• 04/08/2024 - updates to the file description and arxiv paper
• 05/06/2024 - global forces/geo added for all runs
• 01/05/2024 - force/moments corrected (prior version had incorrect Cs data)
• 18/04/2024 - draft version produced