圆域二层准地转轮廓动力学:非稳态上层屏蔽朗肯涡旋的非线性演进(英文)

Two-layer Quasi-geostrophic Contour Dynamics in a Round Domain:Nonlinear Evolution of Unsteady Upper-layer Shielded Rankine Vortex

扩展了圆域中涡旋流动的两层准地转轮廓动力学方法。阐述控制方程模型及其一些基本特性的数值实现。通过拟稳态线性稳定性分析,得出对称潜涡流小于4线的间断潜涡流分布情况。对于非稳定上层屏蔽朗肯旋涡情况的实验结果进行讨论,结果发现,支配扰动波长的变化导致在涡旋底部中心为主的上部旋涡结构中心的初始位移。

To study the vortex flows a two-layer quasi-geostrophic version of the contour-dynamics method was extended in a round domain.Governing equations of the model was setup,and some basic features of the numerical implementation were presented.Linear stability analysis was made for the case of axially symmetric potential vorticity（PV） distributions with less than four lines of PV discontinuity.The case of unsteady upper-layer shielded Rankine vortex was discussed.The results were shown that there was the initial displacement of the center of above vortex structure from the basin center in changes of dominated disturbance wave length.