Offres de Thèses et Postdocs

Dans le cadre de cette thèse, on propose de s’intéresser à la représentation de la turbulence en régime très stable en altitude ; peu de travaux de recherches se sont en effet intéressés à ces conditions. Contact : didier.ricard@meteo.fr

The Laboratory of Fluid Mechanics and Acoustics (CNRS, Ecole Centrale de Lyon) is seeking a highly qualified candidate for a post-doctoral research fellowship regarding the development of grid- refinement techniques for high-fidelity Lattice Boltzmann aeroacoustics simulations.

This PhD position is opened within the SICTAG project (2019-2022) for “Innovative and connected decision aid system and efficient real-time management of wind tower farm in Centre-Val de Loire region”. The Phd Student is

The project consists in the development and the numerical implementation of suitable turbulence modelling techniques to allow accurate unsteady complex flow simulations in hydraulic turbine components. The present study will take place in the MOST research team, internationally known for its work in the field of numerical simulation of turbulent flows. The candidate will have access to the local, French (GENCI) and European (PRACE) computational centers. Moreover, this project will be conducted in close collaboration with the Center Of Excellence (COE) in Hydraulic of General Electric Renewable Energy, located in Grenoble. The position is available immediately.

A two-year postdoc position (renewable) is available at the University of Minnesota (Minneapolis, USA) to study experimentally inertial particle transport in both turbulent and biomedical flows, using optical and medical imaging (PIV, PTV, MRI). There will be opportunities for laboratory studies as well field and in vivo studies. For information please contact Filippo Coletti, fcoletti@umn.edu

The present project funded by DGA aims at producing a large set of experimental data enabling to disentangle the role of the different control parameters relevant to the problem of aerosols settling in turbulent flows.

In the project, Experimental Astrophysical Research into Terrestrial growtH (EARTH), we will investigate the growth processes in protoplanetary disks from the point of view of granular physics. In particular we want to study the effect of tribocharging, i.e. the exchange of electrical charge between particles during collisions, which could offer a way to overcome the meter-sized barrier as it can dramatically increase growth rates.

The CORIA and LOMC laboratories have opening for post-doctoral fellowships in theoretical Hydrodynamics starting October 2019. The work consists in the modeling of hydrodynamic instabilities of Taylor-Couette flows (LOMC) and jet flows (CORIA) both flows with ferrofluids in external magnetic fields.

Le post-doctorant fera partie de l'équipe ERC Fludyco, dont l'objectif général est de mieux appréhender les différents aspects de la dynamique des fluides au sein des noyaux planétaires en combinant approches théoriques, expérimentales, et numériques. Il travaillera sous la supervision de Benjamin Favier et Michael Le Bars.

The thesis project aims to investigate the effect of the radial temperature gradient on turbulence in the T aylor-Couette flow between two coaxial differentially rotating cylinders.

LEGI sponsors Postdoctoral Fellowship to provide research opportunities for those who have earned a Ph.D. in an appropriate area in the past three years. The candidate is expected to interact with LEGI faculty in research projects of mutual interest.

We propose to study how mixing is affected by diffusiophoresis in a Rayleigh-Bénard cell. The config- uration chosen is a long cell, where the velocity is almost 2D just above the instability threshold, and where multiple convection cells are present. The geometry of the cell is very similar to the one used by Solomon & Gollub [4].

This projects aims at developing solid theoretical foundations for wave turbulence systems and modelling experiments in wave turbulence performed in laboratory by partners of this collaboration. The applicant will perform large-scale numerical simulations of different wave systems and confront numerical and theoretical results coming from WWT. Depending on the candidate profile, kinetic wave equations will also be studied numerically or theoretically.

The objective of the postdoc is to study (experimentally and in situ) the influence of turbulence on zooplankton behaviour.

This project aims at bringing new insights to improve the trajectory prediction of space debris re-entry by focusing on the effect of slippage.

This study is part of a national (ANR) research program entitled QUTE-HPC (QUantum Turbulence Explo- ration by High-Performance Computing). The project gathers 10 researchers from physics and mathematics and is aimed at providing a new state-of-the-art for the mathematical-physical modelling and High Perfor- mance Computing (HPC) of Quantum Turbulence (QT) in superfluid quantum fluids, such as superfluid He-

Over the last decades, topology has brought new light to linear dynamics, with the discovery of new classes of waves, and an explanation for peculiar propagating modes whose emergence were up to now mysterious. These ideas have just begun to impact geophysical f luid dynamics, with application to equatorial phenomena (see figure). A variety of potential manifestations of topology in fluid waves remain now to be found. This is the purpose of this post-doctoral proposal.

The Post Doctoral Fellow will be part of a team covering simulations, experiments and theory and carrying out concurrent studies of, comparisons between and modeling of various turbulent flows. Research directed towards industrial applications is also possible as the project is also concerned with new turbulent flow technology in various industrial sectors.

The project consists in the development and the numerical implementation of suitable immersed boundary methods for computational aeroacoustics, to allow accurate simulations of both the flow and the sound it produces (or that propagates in it).

Several three-years post-doctoral positions are opened in the Fluminance Inria team, (INRIA Rennes, France) to work within the ERC project “Stochastic Transport in Upper Ocean Dynamics” (STUOD) in collaboration with Ifremer and Imperial College London.

The aim of the present project is to identify the importance of non-linear effects in the evolution of the wave pattern. Among them, the shift towards larger wavelength and smaller frequency for increasing distances, a phenomenon known as frequency downshift. This nonlinear effect is well-documented in the oceanic literature (Huang et al. 1996) and several mechanisms have been proposed to explain its physic

Le projet vise à caractériser et à quantifier la dynamique d’un écoulement turbulent sur un profil de pale d’éolienne en fonction de l’écoulement amont. Ce dernier peut être un écoulement turbulent classique (couche limite atmosphérique), ou alors un écoulement peuplé par des familles de Structures Cohérentes (SC) produites par des éoliennes situées en amont.

The proposed research subject deals with the application of deep machine learning in the context of Large-Eddy Simulations (LES). This approach relies on the idea of solving only the largest scales of the flow and modeling the effect of small scales, either by phenomenological techniques, or by directly estimating the solution residue after filtering (as in the case of multi-scale VMS stabilized variational formulations).

The goal of this project is to improve our understanding of this turbulent multiphase flow, suing a multiscale experimental approach, studying the spray from the near-field of the atomizer, where interfacial instabilities form on the liquid jet, to the far-field, where droplets are dispersed by the turbulent phase.

The post-doctoral fellow will have to develop and run an experimental setup aiming at forcing a turbulent flow under rotation in a regime of inertial wave turbulence.

Several PhD grants available on «Data assimilation, Learning and stochastic parametrization of ocean models through high-resolution observations»

The efficiency of plasma actuators depends to a large extent on their positions on the wall, as well as on numerous other control hyper-parameters (number of electrodes, distances between them, potential difference or electrical power, shape of

This thesis will contribute to the development of realistic closed-loop control strategies for unsteady turbulent flows. Applications include the drag reduction around profiles (by attaching the boundary layer or delaying its separation), the reduction of radiated noise, the flow vectorization to improve the maneuverability or to remove some of the moving air spoilers, the decrease of vibrations induced by dynamic stall, etc.

This thesis will contribute to the development of realistic closed-loop control strategies for unsteady turbulent flows. Applications include the drag reduction around profiles (by attaching the boundary layer or delaying its separation), the reduction of radiated noise, the flow vectorization to improve the maneuverability or to remove some of the moving air spoilers, the decrease of vibrations induced by dynamic stall, etc.

The objective of this numerical thesis is to develop mathematical modeling and 3D numerical simulations with two different approaches (Euler-Lagrange and Euler-Euler) in order to develop closure models for both phases (liquid and non-spherical particles).

This subject concerns the risks to human health related to airborne microparticles which nature can be diverse (inert, chemical, biological or radioactive). More precisely the objective is to understand the mechanisms responsible for the resuspension of microparticles from free surfaces, when they are submitted to aerodynamic transient events such as airflow acceleration. Therefore this study aims at better understanding and controlling the risks associated with indoor airborne contaminations.

The main objective of the present proposal is to develop feasible efficient active drag reduction strategies based on chaos control concepts. The methodology we introduce is new and promises to be interesting in wall turbulence and active drag control research.

The diversity of geochemical signatures in lava samples collected on Earth suggests that its silicate mantle is heterogeneous at various scales. However, such an interpretation of the geochemical data requires a consistent geodynamic frame to explain the possible survival or the disappearance of mantle heterogeneities.

Bio-based construction materials, formed by the dispersion of vegetal elements (wood, hemp, cellulose wadding, straw, etc) in a cementitious matrix, have the advantage of being light and made of partially recycled and recyclable materials.

The project aims at developing the numerical tools required to achieve fully nonlinear optimal control of MHD flows. These tools will be used to identify "minimal dynamo seeds" in simple swirling flows relevant to stellar systems, i.e. challenge the stability of such flows with respect to initial magnetic fields of arbitrary amplitude and structure.

This PhD research project aims to develop a new methodology for forecasting the transport and dispersion of macro- and micro-plastic litter drifting with currents in marine coastal environments in order to manage pollution risks and their mitigation.

In this PhD thesis, it is proposed to study the local structure of a dispersed-stratified flow of an emulsion in a plane Couette device. In addition to its generic nature, this setup allows the study of the flow features and phase distribution over long times. In the homogeneous dispersed-flow configuration, it can be used to characterize the rheology of the emulsion in a wide range of concentration, from the dilute case to the glass transition and beyond.

We seek an exceptional PhD candidate with the relevant background, motivation and ability to undertake a challenging, high-performance computing fluid-dynamics oriented programme of research within the Wind & Marine Energy Systems & Structures comprehensive doctoral training programme (CDT)* at the University of Strathclyde (Glasgow, UK).

Within this project, the post-doctoral fellow will contribute to the improvement of the representation of the Marine Atmospheric Boundary Layer (MABL) and turbulent fluxes in atmospheric models by developing and testing a parameterization of the impact of sea sprays.

A postdoctoral position is open at the Laboratoire de Mécanique des Fluides et d’Acoustique (LMFA, Ecole Centrale de Lyon). The project is devoted to the settling of spheroidal (rod-like or disc-like) particles in a homogeneous isotropic turbulent flow.

Thermal and compressible flows are characterized by inhomogeneous density fields that are usually difficult to measure. One experimental technique aiming at measuring instantaneous and averaged 3D density fields is the 3D Background Oriented Schlieren (3DBOS), developed at ONERA over the past ten years.