Eventos Anais de eventos
EPTT 2024
14th Spring School on Transition and Turbulence
Resolvent analysis of coherent structures in the atmospheric boundary layer considering Coriolis effects
Submission Author:
Matheus Tozo de Araujo , PR
Co-Authors:
Matheus Tozo de Araujo, Livia S. Freire, Leandro Franco de Souza, André Cavalieri
Presenter: Livia S. Freire
doi://10.26678/ABCM.EPTT2024.EPT24-0032
Abstract
The identification and characterization of large-scale coherent structures of turbulent flows is a problem that demands extensive field measurements or sophisticated numerical simulations, especially when it is referred to highly turbulent and variable flows like the atmospheric boundary layer (ABL). In this study, we explore the efficacy of Resolvent Analysis as a cost-effective means to model ABL coherent structures, leveraging only the mean flow field of the ABL. The Resolvent analysis uses the singular value decomposition of the linearized Navier-Stokes operator, treating nonlinear terms as external forcing. This decomposition yields response modes directly correlated with the most energetic coherent structures of the flow. To validate this approach, we compare its outcomes with modes obtained through Spectral Proper Orthogonal Decomposition (SPOD) applied to detailed numerical data from Large-Eddy Simulations (LES) of a theoretical channel, serving as an initial approximation of the ABL. The influence of the Coriolis force in the fluid flow is analyzed and results where resolvent analysis exhibits the closest agreement with SPOD demonstrate its potential as a cost-effective tool for characterizing ABL coherent structures.
Keywords
turbulent flows, atmospheric boundary layer, Large Eddy Simulation, Resolvent Analysis, Proper Orthogonal Decomposition
