Onset of coherent oscillations in turbulent Rayleigh-Bénard convection.

نویسندگان

  • X L Qiu
  • P Tong
چکیده

We report temperature cross correlation and velocity profile measurements in the aspect-ratio-one convection cell filled with water. A sharp transition from a random chaotic state to a correlated turbulent state of finite coherence time is found when the Rayleigh number becomes larger than a critical value Ra(c) approximately equal to 5 x 10(7). The experiment reveals a unique mechanism for the onset of coherent oscillations in turbulent Rayleigh-Bénard convection.

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عنوان ژورنال:
  • Physical review letters

دوره 87 9  شماره 

صفحات  -

تاریخ انتشار 2001