General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DRF-24-0355
Direction
DRF
Thesis topic details
Category
Condensed Matter Physics, chemistry, nanosciences
Thesis topics
Experimental study of boundary layers in turbulent convection by Diffusive Waves Spectroscopy
Contract
Thèse
Job description
The aim of this thesis is to carry out the first experimental measurement of the energy dissipated in the boundary layers during turbulent convection in the Rayleigh-Bénard configuration. Indeed, some theories assert that this quantity controls the heat flux transported from the hot wall to the cold wall, while the efficiency of turbulent transport in convection is the subject of debate. Yet the properties of turbulent transport are essential to understanding the dynamics of climate and many astrophysical objects.
To estimate the energy dissipated, we need to be able to measure the norm of the velocity gradient. This quantity is difficult to access with conventional anemometry techniques, which measure velocity fields with limited resolution. These gradients are also expensive to obtain numerically over long time scales. But we have developed a technique for directly measuring the norm of velocity gradients using Multiple Scattering Spectroscopy. This will enable us to measure dissipative structures and the rate of energy dissipation in boundary layers.
University / doctoral school
Physique en Île-de-France (EDPIF)
Paris-Saclay
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2024
Person to be contacted by the applicant
AUMAITRE Sébastien sebastien.aumaitre@cea.fr
CEA
DRF/IRAMIS/SPEC/SPHYNX
Tutor / Responsible thesis director
AUMAITRE Sébastien sebastien.aumaitre@cea.fr
CEA
DRF/IRAMIS/SPEC/SPHYNX
En savoir plus
https://iramis.cea.fr/Pisp/sebastien.aumaitre/
https://iramis.cea.fr/spec/sphynx/