Department of Physics, University of Illinois at Urbana-Champaign, Loomis Laboratory of Physics, 61801-3080, USA.
Phys Rev Lett. 2012 Aug 17;109(7):074502. doi: 10.1103/PhysRevLett.109.074502. Epub 2012 Aug 16.
We investigate the effect of weak rotation on the large-scale circulation (LSC) of turbulent Rayleigh-Bénard convection, using the theory for cessations in a low-dimensional stochastic model of the flow previously studied. We determine the cessation frequency of the LSC as a function of rotation, and calculate the statistics of the amplitude and azimuthal velocity fluctuations of the LSC as a function of the rotation rate for different Rayleigh numbers. Furthermore, we show that the tails of the reorientation PDF remain unchanged for rotating systems, while the distribution of the LSC amplitude and correspondingly the cessation frequency are strongly affected by rotation. Our results are in close agreement with experimental observations.
我们利用之前研究的低维随机流动模型的理论,研究了弱旋转对湍流传热瑞利-贝纳德对流大尺度环流(LSC)的影响。我们确定了 LSC 停止的频率作为旋转的函数,并计算了不同瑞利数下 LSC 的幅度和角向速度波动的统计数据作为旋转速率的函数。此外,我们表明,旋转系统的重新取向 PDF 的尾部保持不变,而 LSC 幅度的分布以及相应的停止频率受到旋转的强烈影响。我们的结果与实验观察结果非常吻合。