کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
650599 1457292 2012 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Passive scalar advection in the vicinity of two point vortices in a deformation flow
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Passive scalar advection in the vicinity of two point vortices in a deformation flow
چکیده انگلیسی

The dynamics of passive fluid particles in the vicinity of two point vortices with arbitrary intensities, embedded in a steady external deformation flow, is studied. The motion of passive fluid particles is described by a nonintegrable 1.5 degrees of freedom dynamical system. Though the external flow is stationary, the additional half degree of freedom appears because the vortices’ motion about their stationary positions is periodic. Then, this periodic motion plays the role of a periodic perturbation for the system describing the passive particle dynamics. Therefore, chaotic advection of passive fluid particles in the vicinity of these two vortices can occur. If the vortices, however, are situated at their stationary positions, they become motionless, and the dynamical system describing the passive particles’ dynamics is also stationary. In the case of motionless vortices, a classification of the phase portraits of the passive particle motion is conducted by analyzing the number of critical points. When the vortices do not lie at their stationary position, the system becomes nonstationary. In this case, the existence of impenetrable transport barriers for chaotic advection is shown. These barriers are destroyed when stochastic layers merge; these layers widen as the deviation of the vortex position from the stationary points, increases. The efficiency of chaotization is analyzed by means of Poincaré sections and accumulated Lyapunov exponents.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Mechanics - B/Fluids - Volume 34, July–August 2012, Pages 121–130
نویسندگان
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