• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nonlinear processes in geophysics >Parametric resonance in the dynamics of an elliptic vortex in a periodically strained environment
【24h】

Parametric resonance in the dynamics of an elliptic vortex in a periodically strained environment

机译：椭圆形涡旋动力学在周期性应变环境中的参数共振

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The model of an elliptic vortex evolving in a periodically strained background flow is studied in order to establish the possible unbounded regimes. Depending on the parameters of the exterior flow, there are three classical regimes of the elliptic vortex motion under constant linear deformation: (i)?rotation, (ii)?nutation, and (iii)?infinite elongation. The phase portrait for the vortex dynamics features critical points which correspond to the stationary vortex not changing its form and orientation. We demonstrate that, given superimposed periodic oscillations to the exterior deformation, the phase space region corresponding to the elliptic critical point experiences parametric instability leading to locally unbounded dynamics of the vortex. This dynamics manifests itself as the vortex nutates along the strain axis while continuously elongating. This motion continues until nonlinear effects intervene near the region associated with the steady-state separatrix. Next, we show that, for specific values of the perturbation parameters, the parametric instability is effectively suppressed by nonlinearity in the primal parametric instability zone. The secondary zone of the parametric instability, on the contrary, produces an effective growth of the vortex's aspect ratio.
机译：为了建立可能的无界状态，研究了在周期性应变的背景流中演化的椭圆形涡旋模型。根据外部流的参数，在恒定的线性变形下，椭圆涡旋运动有三种经典形式：（i）旋转，（ii）螺母化和（iii）无限伸长。涡旋动力学的相图具有临界点，这些临界点与固定涡旋相对应，而不会改变其形式和方向。我们证明，给定外部变形叠加的周期性振动，对应于椭圆临界点的相空间区域会经历参数不稳定性，从而导致涡旋局部无界的动力学。当涡流沿着应变轴不断延伸时，这种动力学表现出来。这种运动一直持续到非线性效应介入与稳态分离线相关的区域附近为止。接下来，我们表明，对于摄动参数的特定值，原始参数不稳定区域中的非线性有效地抑制了参数不稳定。相反，参数不稳定性的次要区域会有效增加涡流的纵横比。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号