English

Actuation response model from sparse data for wall turbulence drag reduction

Fluid Dynamics 2019-09-19 v1

Abstract

We compute, model, and predict drag reduction of an actuated turbulent boundary layer at a momentum thickness based Reynolds number of Re{\theta} = 1000. The actuation is performed using spanwise traveling transversal surface waves parameterized by wavelength, amplitude, and period. The drag reduction for the set of actuation parameters is modeled using 71 large-eddy simulations (LES). This drag model allows to extrapolate outside the actuation domain for larger wavelengths and amplitudes. The modeling novelty is based on combining support vector regression for interpolation, a parameterized ridgeline leading out of the data domain, scaling from Tomiyama and Fukagata (2013), and a discovered self-similar structure of the actuation effect. The model yields high prediction accuracy outside the training data range.

Keywords

Cite

@article{arxiv.1909.08310,
  title  = {Actuation response model from sparse data for wall turbulence drag reduction},
  author = {Daniel Fernex and Richard Semaan and Marian Albers and Pascal S. Meysonnat and Wolfgang Schröder and Bernd R. Noack},
  journal= {arXiv preprint arXiv:1909.08310},
  year   = {2019}
}
R2 v1 2026-06-23T11:18:56.838Z