A POD-based analysis of turbulence in the reduced nonlinear dynamics system

2nd Multiflow Summer School on Turbulence

Nikolaidis, M.-A.^1 ; Farrell, B.F.^2 ; Ioannou, P.J.^1 ; Gayme, D.F.^3 ; Lozano-Durán, A.^4 ; Jiménez, J.^4

University of Athens, Department of Physics, Panepistimiopolis, Zografos, Athens

15784, Greece^1

Department of Earth and Planetary Sciences, Harvard University, Cambridge

MA

02138, United States^2

Department of Mechanical Engineering, Johns Hopkins University, Baltimore

MD

21218, United States^3

School of Aeronautics, Universidad Politécnica de Madrid, Madrid

28040, Spain^4

关键词: Nonlinear dynamics system;    POD analysis;    POD modes;    Proper orthogonal decompositions;    Reduced model;    Self-sustaining mechanisms;    Turbulent state;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/708/1/012002/pdf
DOI  :  10.1088/1742-6596/708/1/012002

来源: IOP

【 摘 要 】

The structure of turbulence in a reduced model of turbulence (RNL) is analyzed by means of a Proper Orthogonal Decomposition (POD modes). POD analysis was carried out on two different components of the flow, the roll/streak and the perturbation structure. The POD structure in both RNL and direct numerical simulations (DNS) is similar and this correspondence suggests that the dynamics retained in RNL are the essential dynamical ingredients underlying the self-sustaining mechanism of the turbulent state.