论文标题
在湍流热对流中的螺旋速度波动和大规模循环
Helical velocity fluctuations and large-scale circulation in turbulent thermal convection
论文作者
论文摘要
结果表明，在雷利数的中等和大值（分布式混乱和缩放）下，螺旋力动力学主导湍流热对流中速度波动的光谱分布。湍流的雷利 - 贝纳德对流中的大规模循环（风）对螺旋性动力学尤其敏感，其混乱的逆转可能与平均螺旋符号的逆转有关（长期以来对反射对称性的ergodic恢复）。为了基于螺旋分布的第二阶矩的绝热不变性，使用了自由大气对流的实验实验和测量结果的结果。在这种情况下还讨论了地磁场偶极子的变异性和逆转，并且已经建立了数值模拟的结果和观察数据的结果。
It is shown that helicity dynamics dominates spectral distribution of the velocity fluctuations in turbulent thermal convection at moderate and large values of the Rayleigh number (distributed chaos and scaling respectively). The large-scale circulation (wind) in the turbulent Rayleigh-Bénard convection is especially sensitive to the helicity dynamics and its chaotic reversals can be associated with the reversals of the mean helicity sign (the ergodic restoration of the reflectional symmetry in a long run). Results of the laboratory experiments and measurements in the free atmospheric convection have been used in order to support the theoretical considerations based on the adiabatic invariance of the second order moment of the helicity distribution. The geomagnetic field dipole variability and reversals have been also discussed in this context and good agreement with results of numerical simulations and observational data has been established.
