Ability of a low-dimensional model to predict geometry-dependent dynamics of large-scale coherent structures in turbulence

作者：Bai Kunlun; Ji Dandan; Brown Eric^*

来源：Physical Review E, 2016, 93(2): 023117.

DOI：10.1103/PhysRevE.93.023117

We test the ability of a general low-dimensional model for turbulence to predict geometry-dependent dynamics of large-scale coherent structures, such as convection rolls. The model consists of stochastic ordinary differential equations, which are derived as a function of boundary geometry from the Navier-Stokes equations [Brown and Ahlers, Phys. Fluids 20, 075101 (2008); 20, 105105 (2008)]. We test the model using Rayleigh-B ' enard convection experiments in a cubic container. The model predicts a mode in which the alignment of a convection roll stochastically crosses a potential barrier to switch between diagonals. We observe this mode with a measured switching rate within 30% of the prediction.

• 出版日期2016-2-26