Offres de Thèses et Postdocs

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 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 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.

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

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.

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.

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.

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

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).

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.

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.

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.

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.

The proposed project aims at investigating the characteristics and evolution of the helical vortex wake generated by a three-bladed rotor operating in the wind turbine regime, and its effect on a second rotor placed downstream, in terms of efficiency and fatigue.

The School of Science and Engineering at Reykjabik University (Iceland) is looking for a PhD student to work on the project “Lagrangian Dispersion in Mixed Convective Turbulence “.

the present research work aims at improving the analysis of complex flow around bodies at high speed, including configurations such as space vehicles, using numerical simulations.

The metal additive manufacturing (AM) market has been on the rise for several years, particularly for the aeronautic, medical, automotive sector..., enhancing the need of metal powders with specific particle size distributions and of good quality (spherical, without porosity, of homogeneous chemical composition and without pollution). Among the several atomization technologies that have emerged in recent decades for the production of metal powders, the EIGA (Electrode Induction melting Gas Atomization) process is particularly appealing. This process allows atomizing so-called "reactive" alloys such as titanium alloys, thanks to induction melting without crucible, which limits or even eliminates any pollution linked to the process.

The present research work aims for improving the analysis of complex flow configurations which are observed for space launchers and space vehicles using numerical tools.

This project aims at providing numerical and theoretical support to two experimental groups of the SIMONS Collaboration Wave Turbulence (see below).

The National Institute of Oceanography and Applied Geophysics - OGS and the University of Trieste are issuing a call for applications to 1 PhD positions in EARTH SCIENCE, FLUID-MECHANICS AND MATHEMATICS. INTERACTION AND METHODS (Cycle XXXVII - Academic year 2021-2022). The positions come with scholarship and will be carried out at the Division of Oceanography of the OGS. Applications close on June 7th, 2021 at 13.00 CET.

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 synthetic turbulent inflow conditions for high-fidelity Lattice Boltzmann simulations. Such methods have been developed in the context of NavierStokes approaches at the laboratory. The objective is here to adapt and extend those methods in the context of LBM, with a particular attention paid to the generation of noise.The successful candidate will be in charge of the development and implementation of turbulent inflow conditions in an in-house LB code (written in C++). Validations and evaluations will be carried-out on cases of increasing complexity: isolated boundary layer, compressor cascade and a fan configuration.

An aerodynamic study for transport (aerial, terrestrial) or energy (wind turbines etc.), aimed at minimising energy costs (of transport) or maximising the produced power, requires that one educes the fluid flow upstream of the object that is to be designed, on said object and downstream of the object. The downstream part of the flow is commonly termed a wake. A precise description of the wake un a body (a vehicle, a turbine etc.) is fundamental in the understanding of the lift and the drag exerted by the flow on said object. Wakes can be investigated numerically or experimentally in rather complex and realistic geometries.

We propose a PhD position to explore potentially different research tracks at the crossroad of Physics and machine learning: (i) Noisy, scarce and partial observations, (ii) Training algorithm to enforce physical properties, (iii) Physical applications.

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.

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.

Ce projet vise à apporter des éléments concrets de recherche fondamentale pour analyser, modéliser et prédire la dynamique des fluides et le mélange scalaire associé, des jets dilués à l’hydrogène. Le cas spécifique des effets de diffusion différentielle sera abordé.

The aim of the present project is to develop an efficient solid wall treatment for LBM, including turbulent wall models. Several issues will be addressed, among which:• interpolation methods used within the Immersed-Boundary Method (IBM) or Cartesian meshes framework for solid boundary treatment [1-2]• use of a turbulent wall model in conjunction with immersed solid boundaries [3]• reconstruction of the density distribution functions of LBM at boundaries nodeswithin this framework (accuracy, mass conservation, ...)• reconstruction of macroscopic quantities on the solid surface for post-processing purposes (eg. calculation of aerodynamic forces applied on an airfoil)• extension to moving/deforming solid boundaries

This thesis will focus on internal tidal waves (at diurnal and semi-diurnal frequencies), and may further extend to other type of ocean internal wave (e.g. near-inertial waves).

Le projet de R&D SLITHER (financement région AURA) s’inscrit dans une problématique persistante en maintenance aéronautique : le décapage automatisé complet des aéronefs. Aujourd’hui, le décapage des surfaces des aéronefs n’est toujours pas pleinement automatisable du fait de l’impossibilité de gérer la variabilité des couches de peinture, des formes des appareils et de la difficulté d’accès à certaines zones en environnement complexe, en particulier dans les ailes des avions.

The postdoc position is offered within Team CaliSto at Inria Sophia Antipolis Méditerranée. The team is working on the stochastic modeling applied to single-phase and multiphase flows through complex stochastic differential equations. This is done in collaborations with researchers that share interest in environmental applications (including meteorologists, hydro-physicists, physicists specialized in turbulence and two-phase flows modeling).

We invite doctoral students to apply for a post-doctoral fellowship from the Institute of Mechanics and Engineering of Aix Marseille University (1 year, from October 2021 to October 2022).