论文标题
液体金属中的开普勒湍流的角动量传输
Angular Momentum Transport by Keplerian Turbulence in Liquid Metals
论文作者
论文摘要
我们报告了一项实验室研究，该研究通过限制在薄磁盘中的电动传导流体的湍流对角动量的运输。当施加到液态金属的电磁力足够大时时，角动量的相应体积注入会产生湍流，其特征在于时间平均的开普勒旋转速率$ \barΩ\ sim r^sim r^{ - 3/2} $。确定了对局部角动量转运的两种贡献：一个是由边界的存在引起的多型再循环，另一个是由散装中的湍流波动引起的。后者独立于流体的分子粘度产生有效的角动量传输，并导致Kraichnan的预测$ \ text {nu}_ω\ propto \ sqrt \ sqrt {\ text {tak {ta}} $。因此，在这种所谓的最终状态中，该实验提供了类似于吸积盘的配置，从而可以预测开普勒湍流引起的增生率。
We report a laboratory study of the transport of angular momentum by a turbulent flow of an electrically conducting fluid confined in a thin disk. When the electromagnetic force applied to the liquid metal is large enough, the corresponding volume injection of angular momentum produces a turbulent flow characterized by a time-averaged Keplerian rotation rate $\barΩ\sim r^{-3/2}$. Two contributions to the local angular momentum transport are identified: one from the poloidal recirculation induced by the presence of boundaries, and the other from turbulent fluctuations in the bulk. The latter produces efficient angular momentum transport independent of the molecular viscosity of the fluid, and leads to Kraichnan's prediction $\text{Nu}_Ω\propto\sqrt{\text{Ta}}$. In this so-called ultimate regime, the experiment, therefore, provides a configuration analogous to accretion disks, allowing the prediction of accretion rates induced by Keplerian turbulence.
