Elena Alekseenko, B. Roux. Risk of wind-driven resuspension and transport of contaminated sediments in a narrow marine channel confluencing a wide lagoon. Estuarine, Coastal and Shelf Science, Elsevier, 2020, 237, pp.106649. ⟨10.1016/j.ecss.2020.106649⟩. ⟨hal-02524483⟩ Plus de détails...
Elena Alekseenko, B. Roux. Risk of wind-driven resuspension and transport of contaminated sediments in a narrow marine channel confluencing a wide lagoon. Estuarine, Coastal and Shelf Science, Elsevier, 2020, 237, pp.106649. ⟨10.1016/j.ecss.2020.106649⟩. ⟨hal-02524483⟩
E. Alekseenko, B. Roux. Wind effect on bottom shear stress, erosion and redeposition on Zostera noltei restoration in a coastal lagoon; part 2. Estuarine, Coastal and Shelf Science, Elsevier, In press, ⟨10.1016/j.ecss.2018.05.022⟩. ⟨hal-01813834⟩ Plus de détails...
E. Alekseenko, B. Roux. Wind effect on bottom shear stress, erosion and redeposition on Zostera noltei restoration in a coastal lagoon; part 2. Estuarine, Coastal and Shelf Science, Elsevier, In press, ⟨10.1016/j.ecss.2018.05.022⟩. ⟨hal-01813834⟩
E. Alekseenko, Bernard Roux. Contribution to remediation of brackish lagoon: 3D simulation of salinity, bottom currents and resuspension of bottom sediments by strong winds. Estuarine, Coastal and Shelf Science, Elsevier, In press, ⟨10.1016/j.ecss.2018.05.021⟩. ⟨hal-01813824⟩ Plus de détails...
This work concerns the modelling and numerical simulation of the 3D salinity and current distribution in a very shallow Mediterranean lagoon subject to strong winds which create intensive resuspension of polluted bottom sediments. We consider wind speeds of 10 m/s and 20 m/s in the two dominant wind directions (N-NW and S-SE). This study is made for different scenarios of flow exchanges with the surrounding hydrosystems: a brackish lagoon on the North (the Etang de Berre), the Cadiere River on the East, and a brackish channel on the South (the Rove channel). The bottom shear stress (BSS) are compared to the BBS threshold given in the literature in terms of the bottom roughness. It permits to determine which kind of bottom sediments (muds and sands) will be resuspended by each wind. The bottom currents permit to predict in which direction the suspended sediments will be moved and where are the sedimentary deposit zones. It provides a guide for the specialists of remediation of the lagoon for a mechanical extraction of sediments in such zones. In addition, numerical experiments have been performed to understand how the salinity distribution depends on the flow exchanges with the two brackish surrounding hydrosystems. This new knowledge will permit the owner of this lagoon to know how to maintain efficiently the level of salinity in the suitable range.
E. Alekseenko, Bernard Roux. Contribution to remediation of brackish lagoon: 3D simulation of salinity, bottom currents and resuspension of bottom sediments by strong winds. Estuarine, Coastal and Shelf Science, Elsevier, In press, ⟨10.1016/j.ecss.2018.05.021⟩. ⟨hal-01813824⟩
E. Alekseenko, Bernard Roux. Numerical simulation of the wind influence on bottom shear stress and salinity fields in areas of Zostera noltei replanting in a Mediterranean coastal lagoon. Progress in Oceanography, Elsevier, 2018, 163, pp.147-160. ⟨10.1016/j.pocean.2017.05.001⟩. ⟨hal-02111578⟩ Plus de détails...
The paper concerns the numerical simulation of the wind influence on bottom shear stress and salinity fields in a semi-enclosed coastal lagoon (Etang de Berre) which is connected to the Mediterranean through a long and narrow channel (called Caronte). Two different scenarios are considered. The first scenario (scen.#1), starting with a homogeneous salinity of S = 20 PSU and without wind forcing, studies a stratification process under the influence of a periodic seawater inflow and a strong freshwater inflow from a hydropower plant (250 m 3 /s). Then, in the second scenario (scen.#2), we study how a strong wind of 80 km/h can destroy the haline stratification obtained at the end of scen.#1. The MARS3D numerical model is used to analyze the 3D current and salinity distribution induced by these three meteorological, oceanic and anthropogenic forcings in this lagoon and in the Caronte channel. The main goal is to determine the bottom shear stress (BSS) in the nearshore areas of Zostera noltei replanting, and to compare it with the threshold for erosion of the bottom sediments for different bottom roughness parameters. The most interesting results concern the four nearshore replanting areas; two are situated on the eastern side of EB and two on the western side. The results of scen.#2 show that all these areas are subject to a downwind coastal jet. The destratification process is very beneficial; salinity always remains greater than 12 PSU for a N-NW wind of 80 km/h and a hydropower runoff of 250 m 3 /s. Concerning BSS, it presents a maximum near the shoreline and decreases along transects perpendicular to the shoreline. There exists a zone, parallel to the shoreline, where BSS presents a minimum (where BSS = 0). When comparing the BSS value at the four control points with the critical value, BSS cr , at which the sediment mobility would occur, we see that for the smaller bottom roughness values (ranging from z 0 = 3.5 Â 10 À4 mm, to 3.5 Â 10 À2 mm) BSS largely surpasses this critical value. For a N-NW wind speed of 40 km/h (which is blowing for around 100 days per year), BSS still largely surpasses BSS cr-at least for the silt sediments (ranging from z 0 = 3.5 Â 10 À4 mm, to 3.5 Â 10 À3 mm). This confirms the possibility that the coastal jet could be a stressor for SAV replanting.
E. Alekseenko, Bernard Roux. Numerical simulation of the wind influence on bottom shear stress and salinity fields in areas of Zostera noltei replanting in a Mediterranean coastal lagoon. Progress in Oceanography, Elsevier, 2018, 163, pp.147-160. ⟨10.1016/j.pocean.2017.05.001⟩. ⟨hal-02111578⟩
Alekseenko Elena, Bernard Roux. Submerged Aquatic Vegetation Restoration in Brackish Ecosystems Subject to Strong Winds and Coastal Jets. Oceanography & Fisheries Open access Journal, 2017, 2 (4), pp.555595. ⟨10.19080/OFOAJ.2017.02.555595⟩. ⟨hal-01813859⟩ Plus de détails...
The bottom shear stress (BSS) in a windy Mediterranean lagoon has been carefully investigated through numerical modelling. BSS maps have been obtained for the entire lagoon. The aim is to compare BSS with its critical value in the near shoreareas selected for SAV replanting which are subject to downwind coastal jets.
Alekseenko Elena, Bernard Roux. Submerged Aquatic Vegetation Restoration in Brackish Ecosystems Subject to Strong Winds and Coastal Jets. Oceanography & Fisheries Open access Journal, 2017, 2 (4), pp.555595. ⟨10.19080/OFOAJ.2017.02.555595⟩. ⟨hal-01813859⟩
Journal: Oceanography & Fisheries Open access Journal
E Alekseenko, B Roux, D Fougere, Paul G. Chen. The effect of wind induced bottom shear stress and salinity on Zostera noltii replanting in a Mediterranean coastal lagoon. Estuarine, Coastal and Shelf Science, Elsevier, 2017, 187, pp.293-305. ⟨10.1016/j.ecss.2017.01.010⟩. ⟨hal-01453377⟩ Plus de détails...
The paper concerns the wind influence on bottom shear stress and salinity levels in a Mediterranean semi-enclosed coastal lagoon (Etang de Berre), with respect to a replanting program of Zostera noltii . The MARS3D numerical model is used to analyze the 3D current, salinity and temperature distribution induced by three meteorological, oceanic and anthropogenic forcings in this lagoon. The numerical model has been carefully validated by comparison with daily observations of the vertical salinity and temperature profiles at three mooring stations, for one year. Then, two modelling scenarios are considered. The first scenario (scen.## 1), starting with an homogeneous salinity of S = 20 PSU and without wind forcing, studies a stratification process under the influence of a periodic seawater inflow and a strong freshwater inflow from an hydropower plant (250 m3/s). Then, in the second scenario (scen.## 2), we study how a strong wind of 80 km/h can mix the haline stratification obtained at the end of scen.## 1. The most interesting results concern four nearshore replanting areas; two are situated on the eastern side of EB and two on the western side. The results of scen.## 2 show that all these areas are subject to a downwind coastal jet. Concerning bottom salinity, the destratification process is very beneficial; it always remains greater than 12 PSU for a N-NW wind of 80 km/h and an hydropower runoff of 250 m3/s. Special attention is devoted to the bottom shear stress (BSS) for different values of the bottom roughness parameter (for gravels, sands and silts), and to the bottom salinity. Concerning BSS, it presents a maximum near the shoreline and decreases along transects perpendicular to the shoreline. There exists a zone, parallel to the shoreline, where BSS presents a minimum (close to zero). When comparing the BSS value at the four replanting areas with the critical value, BSScr, at which the sediment mobility would occur, we see that for the smaller roughness values (ranging from z0 = 3.5 × 10-4 mm, to 3.5 × 10-2 mm) BSS largely surpasses this critical value. For a N-NW wind speed of 40 km/h (which is blowing for around 100 days per year), BSS still largely surpasses BSScr - at least for the silt sediments (ranging from z0 = 3.5 × 10-4 mm, to 3.5 × 10-3 mm). This confirms the possibility that the coastal jet could generate sediment mobility which could have a negative impact for SAV replanting.
E Alekseenko, B Roux, D Fougere, Paul G. Chen. The effect of wind induced bottom shear stress and salinity on Zostera noltii replanting in a Mediterranean coastal lagoon. Estuarine, Coastal and Shelf Science, Elsevier, 2017, 187, pp.293-305. ⟨10.1016/j.ecss.2017.01.010⟩. ⟨hal-01453377⟩
Roux B., Bohbot J., Tran Q. H., Sagaut P.. Prediction of cyclic combustion variability in internal combustion engines via coupled 1D-3D LES methods. E. Oate, J. Oliver and A. Huerta. Proceedings of the 6th European Conference on Computational Fluid Dynamics, pp.5474--5485, 2014. ⟨hal-01307241⟩ Plus de détails...
Roux B., Bohbot J., Tran Q. H., Sagaut P.. Prediction of cyclic combustion variability in internal combustion engines via coupled 1D-3D LES methods. E. Oate, J. Oliver and A. Huerta. Proceedings of the 6th European Conference on Computational Fluid Dynamics, pp.5474--5485, 2014. ⟨hal-01307241⟩
Elena Alekseenko, Bernard Roux, Anton Sukhinov, Richard Kotarba, Dominique Fougere. Nonlinear hydrodynamics in a Mediterranean lagoon. Nonlinear Processes in Geophysics, European Geosciences Union (EGU), 2013, 20 (2), pp.189-198. ⟨10.5194/npg-20-189-2013⟩. ⟨hal-01464721⟩ Plus de détails...
The paper addresses the application of the nonlinear hydrodynamics model (RANS (Reynolds-averaged Navier-Stokes) equations) in a wide semi-enclosed Mediterranean lagoon (Berre lagoon), considering three ă natural forcing functions, i.e., sea tide propagating through a long narrow channel, wind and runoff. Main attention is focused to characteristic velocities (at free surface and bottom) and to free surface elevation associated to each of these three mechanisms, with special attention to the nearshore areas (i.e., in shallow water). The most interesting result concerns wind effects which, due to Berre lagoon bathymetry, give rise to downwind coastal jets, alongshore, in shallow water areas. Such coastal jets were never mentioned before in Berre lagoon literature.
Elena Alekseenko, Bernard Roux, Anton Sukhinov, Richard Kotarba, Dominique Fougere. Nonlinear hydrodynamics in a Mediterranean lagoon. Nonlinear Processes in Geophysics, European Geosciences Union (EGU), 2013, 20 (2), pp.189-198. ⟨10.5194/npg-20-189-2013⟩. ⟨hal-01464721⟩
Tatyana Lyubimova, Bernard Roux, Shunlong Luo, Ya. N Parshakova, Natalya Shumilova. Modeling of the near-field distribution of pollutants coming from a ă coastal outfall. Nonlinear Processes in Geophysics, European Geosciences Union (EGU), 2013, 20 (2), pp.257-266. ⟨10.5194/npg-20-257-2013⟩. ⟨hal-01464728⟩ Plus de détails...
The present study concerns the 3-D distribution of pollutants emitted ă from a coastal outfall in the presence of strong sea currents. The ă problem is solved using the nonlinear Reynolds-averaged Navier-Stokes ă equations in the framework of the k-epsilon model. The constants of the ă logarithmic law for the vertical velocity profile in the bottom boundary ă layer are obtained by processing experimental data from acoustic Doppler ă current profilers (ADCPs). The near-field distribution of pollutants at ă different distances from the diffuser is obtained in terms of the ă ambient flow velocity (steady or with tidal effect) and outfall ă discharge characteristics. It is shown that even in the case where the ă effluent density is substantially lower than the ambient sea water ă density the plume can impact the seabed, creating a risk of pollution of ă removable bottom sediments.
Tatyana Lyubimova, Bernard Roux, Shunlong Luo, Ya. N Parshakova, Natalya Shumilova. Modeling of the near-field distribution of pollutants coming from a ă coastal outfall. Nonlinear Processes in Geophysics, European Geosciences Union (EGU), 2013, 20 (2), pp.257-266. ⟨10.5194/npg-20-257-2013⟩. ⟨hal-01464728⟩
D.V. Lyubimov, T. P. Lyubimova, R.V. Skuridin, G. Chen, B. Roux. Numerical investigation of meniscus deformation and flow in an isothermal liquid bridge subject to high-frequency vibrations under zero gravity conditions. Computers and Fluids, Elsevier, 2002, 31, pp.663-682. ⟨10.1016/S0045-7930(01)00078-0⟩. ⟨hal-01307320⟩ Plus de détails...
This paper deals with meniscus deformation and flow in an isothermal liquid bridge maintained between two circular rods, when one rod is subject to axial monochromatic vibrations. It concerns a fundamental aspect of the problem of crystal growth from melt by the floating-zone technique which is often considered in weightlessness conditions. In the absence of vibrations the bridge is cylindrical; but due to vibration the mean shape of the meniscus is no more cylindrical and the meniscus oscillates around this mean shape. Two models are developed. First, we take into account the pulsating deformations of the meniscus (free surface), but we assume that the mean shape of meniscus remains cylindrical (i.e., we neglect the influence of vibration on this mean shape). For this simple case, a solution of the problem for the pulsating meniscus deformations and the pulsating velocity field is found in explicit form. For the mean flow, the problem is solved numerically by a finite-difference method. The calculations demonstrate the contribution of two basic mechanisms of mean flow generation due to vibrations, related to the generation of mean vorticity in the viscous boundary layer near the rigid boundaries and surface-wave propagation at a free surface. The intensity of the mean flow induced by surface waves is found to be sharply increasing when the vibration frequency approaches the resonance values that are determined from the explicit form of the solution of pulsation problem. In the second model, we take into account both pulsating and mean deformations of the meniscus. The governing equations for the potential of pulsating velocity and mean velocity, and for the pressure, are solved by using a finite-difference method and a boundary-fitted curvilinear coordinate system fitting the free surface.
D.V. Lyubimov, T. P. Lyubimova, R.V. Skuridin, G. Chen, B. Roux. Numerical investigation of meniscus deformation and flow in an isothermal liquid bridge subject to high-frequency vibrations under zero gravity conditions. Computers and Fluids, Elsevier, 2002, 31, pp.663-682. ⟨10.1016/S0045-7930(01)00078-0⟩. ⟨hal-01307320⟩
Dv Lyubimov, Tp Lyubimova, Sofiane Meradji, Bernard Roux, D Beysens, et al.. 2D unsteady motion and deformation of a gaseous bubble in a vibrating liquid at zero gravity. Le Journal de Physique IV, 2001, 11 (PR6), pp.Pr6--91. ⟨hal-01291556⟩ Plus de détails...
Dv Lyubimov, Tp Lyubimova, Sofiane Meradji, Bernard Roux, D Beysens, et al.. 2D unsteady motion and deformation of a gaseous bubble in a vibrating liquid at zero gravity. Le Journal de Physique IV, 2001, 11 (PR6), pp.Pr6--91. ⟨hal-01291556⟩
Sofiane Meradji, Tp Lyubimova, Dv Lyubimov, B Roux. Numerical simulation of a liquid drop freely oscillating. Crystal Research and Technology, Wiley-VCH Verlag, 2001, 36 (7), pp.729--744. ⟨hal-01291555⟩ Plus de détails...
Sofiane Meradji, Tp Lyubimova, Dv Lyubimov, B Roux. Numerical simulation of a liquid drop freely oscillating. Crystal Research and Technology, Wiley-VCH Verlag, 2001, 36 (7), pp.729--744. ⟨hal-01291555⟩
Dv Lyubimov, Tp Lyubimova, Sofiane Meradji, B Roux. Vibrational control of crystal growth from liquid phase. Journal of Crystal Growth, Elsevier, 1997, 180 (3), pp.648--659. ⟨hal-01291557⟩ Plus de détails...
Dv Lyubimov, Tp Lyubimova, Sofiane Meradji, B Roux. Vibrational control of crystal growth from liquid phase. Journal of Crystal Growth, Elsevier, 1997, 180 (3), pp.648--659. ⟨hal-01291557⟩
Patrick Bontoux, F. Elie, Claude Smutek, E. Crespo, Bernard Roux, et al.. Numerical simulations of buoyancy driven flows in cylinders and cavities for vapour crystal growth. Kluwer Academic Publisher. Physico-Chemical hydrodynamics, Kluwer Academic Publisher, pp.963-995, 1988, NATO ASI Series, Vol 174. ⟨hal-00229875⟩ Plus de détails...
Patrick Bontoux, F. Elie, Claude Smutek, E. Crespo, Bernard Roux, et al.. Numerical simulations of buoyancy driven flows in cylinders and cavities for vapour crystal growth. Kluwer Academic Publisher. Physico-Chemical hydrodynamics, Kluwer Academic Publisher, pp.963-995, 1988, NATO ASI Series, Vol 174. ⟨hal-00229875⟩
