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

[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.

[发布机构] 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