Spectra of near-equilibrium adverse-pressure-gradient turbulent boundary layers

Pozuelo R, Li Q, Schlatter P, Vinuesa R (2023)


Publication Type: Journal article

Publication year: 2023

Journal

Book Volume: 8

Article Number: L022602

Journal Issue: 2

DOI: 10.1103/PhysRevFluids.8.L022602

Abstract

With the availability of new high-Reynolds-number (Re) databases of turbulent boundary layers (TBLs) it has been possible to identify in detail certain regions of the boundary layer with more complex behavior. In this study we consider a unique database at moderately-high Re, with a nearconstant adverse pressure gradient (APG) [Pozuelo et al., J. Fluid Mech. 939, A34 (2022)0022-112010.1017/jfm.2016.715], and perform spectral analysis of the Reynolds stresses, focusing on the streamwise component. We assess different regions of the APG TBL, comparing this case with the zero-pressure-gradient (ZPG) TBL, and identify the relevant scaling parameters as well as the contribution of the scales of different sizes. The small scales in the near-wall region up to the near-wall spectral peak have been found to scale using viscous units. In APG TBLs, the largest scales close to the wall have a better scaling with the boundary-layer thickness (δ99), and they are significantly affected by the APG. In the overlap and wake regions of the boundary layer, the small energetic scales exhibit a good scaling with the displacement thickness (δ∗) while the larger scales and the outer spectral peak are better scaled with the boundary-layer thickness. Also, note that the wall-normal location of the spectral outer peak scales with the displacement thickness rather than the boundary layer thickness. The various scalings exhibited by the spectra in APG TBLs are reported here, and shed light on the complex phenomena present in these flows of great scientific and technological importance.

Authors with CRIS profile

Involved external institutions

How to cite

APA:

Pozuelo, R., Li, Q., Schlatter, P., & Vinuesa, R. (2023). Spectra of near-equilibrium adverse-pressure-gradient turbulent boundary layers. Physical Review Fluids, 8(2). https://doi.org/10.1103/PhysRevFluids.8.L022602

MLA:

Pozuelo, Ramon, et al. "Spectra of near-equilibrium adverse-pressure-gradient turbulent boundary layers." Physical Review Fluids 8.2 (2023).

BibTeX: Download