Halting scale and energy equilibration in two-dimensional quasigeostrophic turbulence
Halting scale and energy equilibration in two-dimensional quasigeostrophic turbulence
复制标题
二维准地转湍流中的停止尺度和能量平衡
DOI：
10.1017/jfm.2013.120
复制
发表时间：
2013
影响因子：
3.7
通讯作者：
D. Dritschel
中科院分区：
文献类型：
--
作者：
R.K. Scott;D. Dritschel
摘要本文考虑了强迫准地转湍流在中间Rossby变形长度范围内的逆能量级联的停止尺度和动能与势能之间的分配，其中变形长度与流动的含能尺度相当。现象学估计的停止规模和平衡能量的强迫耗散系统与一个简单的表示大规模的热阻尼测试对数值积分，并发现描述数值获得的阻尼系数的依赖性差，提出了一个修改后的标度律，更准确地描述的依赖性。阻尼的尺度选择性导致了一个大规模的频谱瓶颈，使能谱变陡，这与以前的hypodiffusive耗散研究一致。据发现，在整个参数范围内考虑，阻塞是在很大程度上不敏感的变形半径的比率，含能尺度。
Abstract The halting scale of the inverse energy cascade and the partition between kinetic and potential energy are considered for the case of forced quasigeostrophic turbulence in the regime of intermediate Rossby deformation length, for which the deformation length is comparable to the energy-containing scales of the flow. Phenomenological estimates for the halting scale and equilibrated energy of the forced–dissipative system with a simple representation of large-scale thermal damping are tested against numerical integrations and are found to poorly describe the numerically obtained dependence on damping coefficient; a modified scaling law is proposed that more accurately describes the dependence. The scale-selective nature of the damping leads to a large-scale spectral bottleneck that steepens the energy spectrum, consistent with previous studies of hypodiffusive dissipation. It is found that, across the parameter range considered, the blocking is largely insensitive to the ratio of deformation radius to the energy-containing scales.