Defect turbulence in inclined layer convection.

نویسندگان

  • Karen E Daniels
  • Eberhard Bodenschatz
چکیده

We report experimental results on the defect turbulent state of undulation chaos in inclined layer convection of a fluid with Prandtl number approximately 1. By measuring defect density and undulation wave number, we find that the onset of undulation chaos coincides with the theoretically predicted onset for stable, stationary undulations. At stronger driving, we observe a competition between ordered undulations and undulation chaos, suggesting bistability between a fixed-point attractor and spatiotemporal chaos. In the defect turbulent regime, we measured the defect creation, annihilation, entering, leaving, and rates. We derive a universal probability distribution function which agrees with the experimental findings.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Defect turbulence and generalized statistical mechanics

We present experimental evidence that the motion of point defects in thermal convection patterns in an inclined fluid layer is well described by Tsallis statistics with an entropic index q ≈ 1.5. The dynamical properties of the defects (anomalous diffusion, shape of velocity distributions, power-law decay of correlations) are in good agreement with typical predictions of nonextensive models, ov...

متن کامل

Statistics of defect motion in spatiotemporal chaos in inclined layer convection.

We report experiments on defect-tracking in the state of undulation chaos observed in thermal convection of an inclined fluid layer. We characterize the ensemble of defect trajectories according to their velocities, relative positions, diffusion, and gain and loss rates. In particular, the defects exhibit incidents of rapid transverse motion which result in power law distributions for a number ...

متن کامل

Whirling hexagons and defect chaos in hexagonal non-Boussinesq convection

We study hexagon patterns in non-Boussinesq convection of a thin rotating layer of water. For realistic parameters and boundary conditions we identify various linear instabilities of the pattern. We focus on the dynamics arising from an oscillatory side-band instability that leads to a spatially disordered chaotic state characterized by oscillating (whirling) hexagons. Using triangulation we ob...

متن کامل

Statistics of defect trajectories in spatio-temporal chaos in inclined layer convection and the complex Ginzburg-Landau equation.

For spatio-temporal chaos observed in numerical simulations of the complex Ginzburg-Landau equation (CGL) and in experiments on inclined-layer convection (ILC) we report numerical and experimental data on the statistics of defects and of defect loops. These loops consist of defect trajectories in space-time that are connected to each other through the pairwise annihilation or creation of the as...

متن کامل

The evolution of co-rotating vortices in a canonical boundary layer with inclined jets

The evolution of co-rotating streamwise vortices in a canonical flat plate turbulent boundary layer ~thickness of the boundary layer d0.99525 mm) is studied. The vortices are produced by an array of inclined jets ~diameter D514 mm) with the same orientation ~skew angle b and pitch angle a of 45°!. The focus of the investigation is on the immediate vicinity of the jet exit and downstream locatio...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Physical review letters

دوره 88 3  شماره 

صفحات  -

تاریخ انتشار 2002