Offres de Thèses et Postdocs

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.

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.

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.

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

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 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.

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).

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.

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 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.

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.

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).

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.

The Collaborative Research Centre TRR 181 "Energy Transfers in Atmosphere and Ocean" invites applications for 30 PhD and Postdoc positions.

Nous recrutons un(e) Ingénieur(e) R&D Post Doc en CDD, dans le cadre d’une étude collaborative avec les laboratoires LEMTA et IJL de l’Université de Lorraine.

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

The present project funded by Direction Generale de l’Armement aims at using this system to systematically study the effect of particles on the carrier turbulent phase for a wide range of particle populations (density, size, loading).

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.

Research area: Large-eddy simulation, turbulence modeling, flow control & turbulent shear flows.Requirements: Strong background in high-fidelity flow modeling techniques (LES/DNS) and turbulence modeling.

In this project, funded by CNES, we will explore Lagrangian transport in a model of surface ocean turbulence including ageostrophic dynamics by means of numerical simulations.

La résolution analytique des équations décrivant la turbulence est actuellement impossible et même l’existence de solutions régulières n’est pas certaine (cf. AMS millennium prize). Côté numérique, la limitation provient du nombre d’échelles mises en jeu qui augmente fortement avec l’intensité de la turbulence. En cas de forte turbulence, les codes ne modélisent donc que les plus grandes échelles et supposent une loi de raccordement pour les échelles plus petites et ce jusqu’à la dissipation visqueuse. Une meilleure compréhension des mécanismes qui gouvernent la turbulence nous permettrait d’obtenir des modèles sous-maille plus pertinents. Pour cela, une des approches choisies par un groupement de laboratoires, dont le Dsbt, consiste en l’étude comparée turbulence classique/superfluide. C’est dans ce cadre que nous proposons une thèse basée sur l’utilisation conjointe de deux diagnostics, visualisation et atténuation de second son, qui nous permettrons d’accéder au champs de vitesse et à la vorticité moyenne.

The LIO Laboratory of Excellence (LabEx) proposes a 2-year post-doctoral position on "Penetrative convection: experiments on a rotating table". Research fields : Fluid dynamics - Geophysics - Convection