Local temperature measurements in turbulent rotating Rayleigh-Bénard convection.

نویسندگان

  • Yuanming Liu
  • Robert E Ecke
چکیده

We present local temperature measurements of turbulent Rayleigh-Bénard convection with rotation about a vertical axis. The fluid, water with Prandtl number about 6, was confined in a cell with a square cross section of 7.3×7.3 cm(2) and a height of 9.4 cm. Temperature fluctuations and boundary-layer profiles were measured for Rayleigh numbers 1×10(7)<Ra<5×10(8) and Taylor numbers 0<Ta<5×10(9). We present statistics of the temperature field measured by a single thermistor located along the vertical centerline of the cell or by an array of thermistors distributed laterally from that centerline. The statistics include the mean temperature, standard deviation, skewness, and the probability distribution functions at various locations in the cell, especially near and inside the thermal boundary layer. The effects of rotation on these quantities are discussed including the presence of a rotation-dependent mean vertical temperature gradient, the negative skewness of temperature fluctuations in the boundary layer, and the horizontal homogenization of temperature.

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عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 84 1 Pt 2  شماره 

صفحات  -

تاریخ انتشار 2011