G2Aero Database of Airfoils - Curated Airfoils

Description

This dataset contains a curated set of 19,164 airfoil shapes from various applications and the data-driven design space of separable shape tensors (PGA space), which can be used as a parameter space for machine-learning applications focused on airfoil shapes. We constructed the airfoil dataset in two main stages. First, we identified 13 baseline airfoils from the NREL 5MW and IEA 15MW reference wind turbines. We reparameterized these shapes using least-squares fits of 8-order CST parametrizations, which involve 18 coefficients. By uniformly perturbing all 18 CST coefficients by +/-20% around each baseline airfoil, we generated 1,000 unique airfoils. Each airfoil was sampled with 1,001 shape landmarks whose x-coordinates followed a cosine distribution along the chord. This process resulted in a total of 13,000 airfoil shapes, each with 1,001 landmarks. In the second phase, we gathered additional airfoils from the extensive BigFoil database, which consolidates data from sources such as the University of Illinois Urbana-Champaign (UIUC) airfoil database, the JavaFoil database, the NACA-TR-824 database, and others. We undertook a thorough pre-processing step to filter out shapes with sparse, noisy, or incomplete data. We also removed airfoils with sharp leading edge and those exceeding our threshold for trailing edge thickness. Additionally, we thinned out the collection of NACA airfoils-- parametric sweeps of NACA airfoils with increasing thickness and camber present in BigFoil database-- by selecting every fourth step in the parameter sweeps. Finally, we regularized the airfoils by reparametrizing them with an 8-order CST parametrization (with 1,001 shape landmarks with x coordinated following cosine distribution along the chord) and removing airfoils with high reconstruction errors. This data pre-processing resulted in a set of 6,164 airfoils. In total, our curated airfoil dataset comprises 19,164 airfoils, each with 1,001 landmarks, and is stored in the curated_airfoils.npz file. Using this curated airfoil dataset, we utilized the separable shape tensors framework to develop a data-driven parameterization of airfoils based on principal geodesic analysis (PGA) of separable shape tensors. This PGA space is provided in PGAspace.npz file.

Resources

Name Format Description Link
0 The curated database of 19,164 airfoils combines the set of 6,164 airfoils from BigFoil database and 13,000 airfoils defined by random perturbations to CST coefficients of baseline airfoils. All airfoils are reparametrized using an 8-order CST parametrization with 1,001 shape landmarks with x coordinated following cosine distribution along the chord. https://data.openei.org/files/6198/curated_airfoils.npz
0 The data-driven design space of separable shape tensors (PGA space), defined by airfoil shapes from curated dataset of airfoils and created using G2Aero package. It can be used as a parameter space for machine-learning applications focused on airfoil shapes https://data.openei.org/files/6198/PGAspace.npz
21 Repository that contains demo notebooks to explore the data. https://github.com/NREL/windAI_bench/tree/main/curated_airfoils

Tags

  • data
  • pga
  • dataset
  • database
  • curated
  • airfoils
  • bigfoil
  • wind-energy
  • g2aero
  • machine-learning
  • parameter-space
  • energy
  • shapes

Topics

Categories