Seiches in lateral cavities with simplified planform geometry: Oscillation modes and synchronization with the vortex shedding
| Autor: | Nicolas Riviere, L. Engelen, Diego Lopez, C. Perrot-Minot, Emmanuel Mignot, Tom De Mulder |
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| Přispěvatelé: | Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Universiteit Gent = Ghent University [Belgium] (UGENT) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Technology and Engineering
Aspect ratio Computational Mechanics Geometry 01 natural sciences 010305 fluids & plasmas FLOWS Longitudinal mode symbols.namesake 0103 physical sciences Froude number [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] FIELD 010306 general physics ComputingMilieux_MISCELLANEOUS Fluid Flow and Transfer Processes Physics CHANNELS Oscillation Mechanical Engineering Condensed Matter Physics Vortex shedding Vortex Transverse plane Mechanics of Materials symbols Physics::Accelerator Physics Dimensionless quantity |
| Zdroj: | Physics of Fluids Physics of Fluids, American Institute of Physics, 2020, 32, pp.085103. ⟨10.1063/5.0016118⟩ PHYSICS OF FLUIDS |
| ISSN: | 1070-6631 1089-7666 |
| DOI: | 10.1063/5.0016118⟩ |
| Popis: | Lateral cavities adjacent to open-channel flows are dead zones located on one side of a main stream. With an approaching flow with a high (subcritical) Froude number, the free-surface of the dead-zone oscillates with high amplitudes and generates a so-called seiche. This configuration is reproduced in a rectangular cavity (with an interface length equal to the main stream channel width) in which the impact of the three dimensionless parameters (Froude number, dimensionless water depth, and geometrical aspect ratio) affecting the seiche is studied experimentally. For all configurations, a natural mode of the cavity is observed, this mode being either longitudinal or transverse, except in the case of a square cavity where bi-directional seiching occurs. Moreover, we show that while the approaching Froude number (0.55 < Fr < 0.7) and dimensionless water depth do not affect the oscillation mode, the selected natural mode is strongly dependent on the geometrical aspect ratio of the cavity. For narrow cavities (small [W + b]/b with W and b the cavity and channel widths, respectively), a longitudinal mode occurs while for wider cavities transverse modes occur, with an increasing number of nodes as the width of the cavity increases. Finally, measuring the time-resolved 2-dimensional field of free-surface deformation in the cavity and the adjacent main stream permits us to identify the vortices shed along the mixing layer at the cavity/main stream interface and thus to analyze the synchronization between the surface oscillation and vortex shedding (at the upstream edge) and impinging (at the downstream edge) processes. |
| Databáze: | OpenAIRE |
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