Offres de Thèses et Postdocs

The wind turbine production in a floating wind farm depends essentially on its position, the wind and the state of the sea. The influence of the state of the sea, in particular, is poorly known, because it has not been an influential factor in the development of installed wind farms. First of all, the influence of the movement of the platform directly affects the production capacity of the wind turbine. But beyond that, it induces significant modifications to the wake, and in the context of commercial farms, where the turbines are not widely spaced, leads to interactions between turbines which are still unknown. As Numerical simulations are very expensive, from numerical simulation and historical data, the environmental conditions can be modeled by stochastic models which are faster to simulate. hus, by combining these stochastic models with the physical model, it is possible to evaluate the uncertainty relating to the key parameters (extractable energy, wake topology).

The post-doc will run a new experimental setup aiming at reaching the weakly non-linear wave turbulence regime in a stratified (and rotating) fluid. The objective is to test the theoretical predictions of the Weak Turbulence Theory which might be relevant to describe the turbulent dynamics of the oceans at small scales but remains controversial.

Les lits fluidisés circulants possèdent des caractéristiques exceptionnelles en termes de transport et de mélange, de mise en contact entre la phase dispersée et le milieu gazeux, d’inertie thermique et de transfert en parois. Ces caractéristiques les rendent très présents dans le domaine de l’énergie notamment pour le développement de procédés innovants qui répondent aux enjeux de la transition énergétique. Les lits fluidisés circulants gaz-solide sont étudiés par le PROMES comme une alternative aux fluides caloporteurs qui sont utilisés pour transporter la chaleur obtenue à partir du rayonnement solaire dans les centrales solaires à concentration notamment dans le cadre des projets européens CSP2 et Next-CSP [1 - 4]. Dans ce procédé, le rayonnement solaire est concentré sur des tubes verticaux au sein desquels circule un mélange gaz-particules. La compréhension et la maitrise des régimes d’écoulements en jeu, et des transferts thermiques associés, sont les verrous scientifiques.

The exchange of viscous fluids induced by a Rayleigh-Taylor instability (RTI) in a confined environment is encountered in a variety of geophysical and industrial problems. For instance, this type of flow is suspected to control the distribution of magma and gas (SO2) released in some types of volcanic eruptions (Stevenson & Blake 1998). Similarly, these exchange flows modify the pressure drop in secondary or enhanced hydrocarbon recovery processes (Joseph et al. 1997).

The postdoctoral fellow will contribute to the development of a stochastic, data-driven model capable of generating high-resolution 3D+1 wind velocity fields. The research will focus on coupling coarse-grid mechanistic simulations with high-frequency local data assimilation using ensemble Kalman filtering techniques. A key challenge will be to reproduce the intermittent, multifractal nature of turbulent flows, crucial for accurate dispersion models in agroecology.

This internship focuses on investigating wall-bounded turbulent flows for heat transfer enhancement applications. The project involves numerical simulations and data analysis to understand the fundamental mechanisms of near-wall turbulence and their impact on heat transfer efficiency.

Projet de thèse (début printemps/automne 2025) ou postdoc (début automne 2025) intitulé:Étude expérimentale de la fonte des glaces en environnement salin stratifié : impact d'un écoulement moyen turbulent et application à la fonte des plateformes glaciaires antarctiquesProjet financé par le projet européen ERC IceAblation. Plus d'informations dans le document en PJ. Merci de m'envoyer un CV, résumé des cours choisis et notes d'examen, et une lettre de motivation (1 page).**************************PhD (sprint/fall 2025 start) or postdoc (fall 2025 start) project entitled:Laboratory modelling of ice melting in stratified salt water: impact of a turbulent mean flow and application to the melting of Antarctic ice shelvesProject funded through the european project ERC IceAblation. See the attached document for more information. Applications should include a short cover letter (1 page), academic transcripts and a CV.

I have a fully-funded PhD studentship available in experimental geophysical fluid dynamics at the University of St Andrews (School of Mathematics and Statistics): "Emergence and equilibration of zonal winds on giant planets: a wave-mean flow interaction approach". It is open to UK and international students, and the anticipated start date is September 2025.