Penta-hepta defect chaos in a model for rotating hexagonal convection.

نویسندگان

  • Yuan-Nan Young
  • Hermann Riecke
چکیده

In a model for rotating non-Boussinesq convection with mean flow, we identify a regime of spatiotemporal chaos that is based on a hexagonal planform and is sustained by the induced nucleation of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlations between the defects in the form of density-dependent creation and annihilation rates of defects. We extract these rates from the distribution function and also directly from the defect dynamics.

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

1 9 Se p 20 02 Penta - Hepta Defect Chaos in a Model for Rotating Hexagonal Convection

In a model for rotating non-Boussinesq convection with mean flow we identify a regime of spatiotemporal chaos that is based on a hexagonal planform and is sustained by the induced nucleation of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlat...

متن کامل

Induced Defect Nucleation and Side-Band Instabilities in Hexagons with Rotation and Mean flow

The combined effect of mean flow and rotation on hexagonal patterns is investigated using Ginzburg-Landau equations that include nonlinear gradient terms as well as the nonlocal coupling provided by the mean flow. Long-wave and short-wave side-band instabilities are determined. Due to the nonlinear gradient terms and enhanced by the mean flow, the penta-hepta defects can become unstable to the ...

متن کامل

Defect Dynamics during a Quench in a BéNard-Marangoni convection System

We report experimental evidence of defect formation and dynamics in a symmetry breaking transition for a conduction–convection Bénard–Marangoni system. As opposite to the behavior of perfect patterns, defects appear to interact in a spatial region, responsible for the formation of bounded states that survive much longer than the characteristic time scales. The analysis of the transient defect d...

متن کامل

Evolution of hexagonal patterns from controlled initial conditions in a Bénard-Marangoni convection experiment.

We report quantitative measurements of both wave number selection and defect motion in nonequilibrium hexagonal patterns. A novel optical technique ("thermal laser writing") is used to imprint initial patterns with selected characteristics in a Bénard-Marangoni convection experiment. Initial patterns of ideal hexagons are imposed to determine the band of stable pattern wave numbers while initia...

متن کامل

Penta-hepta defect motion in hexagonal patterns.

The structure and dynamics of penta-hepta defects (PHD’s) in hexagonal patterns are studied in the framework of coupled amplitude equations for the underlying plane waves. An analytical solution for the phase field of moving PHD is found in the far field, which generalizes the static solution due to Pismen and Nepomnyashchy. The mobility tensor of the PHD is calculated using a combined analytic...

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 90 13  شماره 

صفحات  -

تاریخ انتشار 2003