Hydrodynamic Instability of Spatially Periodic Flows of Homogeneous and Stratified Fluid with Regard for Friction. Formation of Steady-State Vortex Disturbances
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引用次数: 0
Abstract
The stability of spatially periodic flows of homogeneous and stratified fluid is investigated with regard for bottom friction. The Galerkin method with three basis Fourier harmonics is used to solve the stability problem. A system of ordinary differential equations for the amplitudes of the Fourier harmonics is formulated. A solution to the linearized version of the system is obtained and an expression for the increment of disturbance growth is found. It is established that at the nonlinear stage of development the exponential growth of linear disturbances is replaced by the regime of establishing steady-state periodic disturbances in form of closed cells. These disturbances reduce the averaged horizontal velocity of the flow. Analytical expressions for the spatial period and amplitude of steady-state disturbances are obtained.
期刊介绍：
Fluid Dynamics is an international peer reviewed journal that publishes theoretical, computational, and experimental research on aeromechanics, hydrodynamics, plasma dynamics, underground hydrodynamics, and biomechanics of continuous media. Special attention is given to new trends developing at the leading edge of science, such as theory and application of multi-phase flows, chemically reactive flows, liquid and gas flows in electromagnetic fields, new hydrodynamical methods of increasing oil output, new approaches to the description of turbulent flows, etc.
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