Energy-enstrophy stability of β-plane Kolmogorov flow with drag
Energy-enstrophy stability of β-plane Kolmogorov flow with drag
复制标题
带有阻力的β平面柯尔莫哥洛夫流的能量熵稳定性
DOI：
10.1063/1.2958321
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发表时间：
2008
影响因子：
4.6
通讯作者：
W. Young
中科院分区：
文献类型：
--
作者：
Y. Tsang;W. Young
我们开发了一种非线性稳定性方法，即能量熵（EZ）方法，该方法专门用于二维流体力学和由单个亥姆霍兹特征模态组成的基本状态流。该方法应用于受正弦波体力驱动、阻力滞后的β平面流动，阻尼时间尺度为μ−1。标准能量法[H。fuuta和Y. Murakami， J. Phys。Soc。[Jpn. 64, 3725(1995)]证明了层流解在（μ,β）参数空间的某一部分内是单调且全局稳定的。与能量法相比，EZ法在（μ,β）参数空间的更大范围内证明了非线性稳定性。此外，通过惩罚高波数，EZ方法识别出最强烈的放大干扰，比能量方法提供的干扰在物理上更现实。线性不稳定性计算用于确定（μ,β）参数空间的区域，其中流动在无穷小扰动下不稳定。只有很小的差距在…
We develop a nonlinear stability method, the energy-enstrophy (EZ) method, that is specialized to two-dimensional hydrodynamics and basic state flows consisting of a single Helmholtz eigenmode. The method is applied to a β-plane flow driven by a sinusoidal body force and retarded by drag with damping time scale μ−1. The standard energy method [H. Fukuta and Y. Murakami, J. Phys. Soc. Jpn. 64, 3725 (1995)] shows that the laminar solution is monotonically and globally stable in a certain portion of the (μ,β)-parameter space. The EZ method proves nonlinear stability in a larger portion of the (μ,β)-parameter space than does the energy method. Moreover, by penalizing high wavenumbers, the EZ method identifies a most strongly amplifying disturbance that is more physically realistic than that delivered by the energy method. Linear instability calculations are used to determine the region of the (μ,β)-parameter space where the flow is unstable to infinitesimal perturbations. There is only a small gap between the...