My research is currently focusing on two main topics.
Convection from a physics point of view:It's a part of the project TERRA-MWH (ANR-11-ISO4-0004) that consists to study convection in a fluid purely internally heated. We used a microwave device developed by INCDTIM team to achieve non-contact internal heating. It represents a milestone for laboratory experiments since it's the first time that an experiment can reproduce an Earth-like convection. We conducted numerical simulations to validate this innovative prototype and used these simulations to develop new scaling laws. Especially we bridged the gap between Howard's theory of thermal boundary layers and numerical results.
Spin state transition implications on dynamics:Since the observation by James Badro et al. (2003) of an iron spin state transition in Ferropericlase, there are an increasing number of studies about its implications. There was an apparent issue because dynamics and mineral physics studies found a dramatic effect of these electronic transitions while seismologists can't see any discontinuities at the depth given by high pressure experiments. We considered a classical pyrolitic composition and we calculated the effect of Fe2+ spin state transition in Ferropericlase on density. The fact to consider a whole mantle composition enabled us to study different compositions. In particular to include the Fe partitioning between Perovskite and Ferropericlase that were found to vary importantly with pressure. Our calculated density agreed with both PREM density and high pressure and temperature experiments. We found no effect on dynamics so we solved the apparent discrepancy between mineral physics and seismological observations. However new calculations show that if we associate a viscosity change to the Fe partitioning change then it could be responsible of the 1000km depth discontinuity found by seismologists.