Formation of the fine structure of laminated stratified flows
| Autor: | V. G. Baidulov, M. P. Vasil’ev |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Fluid Flow and Transfer Processes
Physics Buoyancy Inertial frame of reference Laplace transform Mechanical Engineering Stratified flows General Physics and Astronomy Stratification (water) Mechanics engineering.material Physics::Fluid Dynamics Viscosity symbols.namesake engineering Froude number symbols Boundary value problem |
| Zdroj: | Fluid Dynamics. 42:921-936 |
| ISSN: | 1573-8507 0015-4628 |
| DOI: | 10.1134/s0015462807060075 |
| Popis: | The process of formation of the fine structure of stratified fluid flows is investigated in detail on the basis of exact solutions of the initial boundary value problems constructed using the Laplace transform. The problems of formation of plane-parallel flows generated in the neighborhood of a plane or a cylinder inclined to the horizontal and moving in translation are considered as model problems. The transformation of the properties of the solutions is studied by successively going over from the model of a homogeneous to that of an inhomogeneous fluid and to the model which takes diffusion of the stratifying admixture into account. It is shown that despite of the smallness of the parameters responsible for the stratification and diffusion effects their contribution with respect to other effects (inertial and viscous forces) is determined not only by the value of the scalar parameters (Froude and Schmidt numbers) but also to a substantial degree by the dynamic factors. Due to the great difference between the scalar parameters four time zones (three zones of small times, namely, viscous, buoyancy, and diffusion times, and the large-time zone) on whose boundaries the flow model changes are distinguished in the study. It is shown that the passage to the limit as t → ∞ is nonuniform for both plane and cylindrical geometry. Transition to steady-state models leads not only to nonuniformity of the double passage to the limit but frequently also to the need to reformulate the boundary conditions. |
| Databáze: | OpenAIRE |
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