Missions

Since 1 October 2022, the LTeN lab (UMR CNRS 6607) has been coordinating the ANR ORCHESTRA program (Topology optimisation of SiC-based 3D architectures for efficient high-temperature heat generation dominated by radiative transfers), which aims to design new sustainable high-temperature heat exchangers based on silicon carbide (SiC). These exchangers can be used as volumetric solar absorbers, which are key components in converting concentrated solar radiation (1-5 MW/m²) into hot air (approximately 1000°C). ORCHESTRA brings together four academic partners around complementary activities: GeM Nantes (multi-scale mechanics, experimental monitoring of crack fronts using rapid optical methods), IFPEN Rueil-Malmaison (topology optimisation/mechanical behaviour of porous media), IRCER Limoges (additive manufacturing of SiC-based porous networks) and LTeN (convective-conductive-radiative topology optimisation, thermo-fluidic behaviour and high-temperature thermal shocks). The design of SiC-based networks combines thermo-fluidic topological optimisation and additive manufacturing. A key factor in ensuring the durability of these 3D SiC architectures is to ensure that they can withstand a large number of thermal cycles (approximately 10,000) at high radiative flux (as in a real solar tower power plant) while maintaining their integrity. To achieve it, a new bench using a 2 kW (1 µm) power laser has been set up in a secure room at LTeN. The samples, all of which are dense, are positioned on a heat-insulated sample holder and heated from the front. Two cameras, infrared and visible, will be used to dynamically monitor changes in temperature and mechanical deformation fields at the rear. The next step is to exploit the various thermal cycles that can be programmed (temperature rises and falls, plateau temperature, heating atmosphere) and compare the measured fields with those obtained from finite element calculations (FreeFEM). It will then be possible to define the thermal loads required to preserve the integrity of the dense SiC ceramics under study. The results will also feed into discussions on future programmes aimed at developing new SiC-based electric radiant heaters capable of operating at temperatures of up to 1600°C.

Activities

- To operate a high-temperature heating bench based on a high-power laser
- To characterise heat flows and temperature fields using infrared thermography (using inverse methods)
- To develop rapid imaging on dense samples
- To propose thermo-chemo-mechanical behaviour laws and criteria that preserve the use of samples.
- To present the results at national and international conferences and ORCHESTRA consortium meetings

Skills

The candidate must:
- Have a PhD in thermal energy or mechanics.
- Have an interest in experimental developments combining high radiative flux, infrared thermography and rapid visible imaging.
- Be organised, independent, rigorous and enjoy working in a multidisciplinary team.
- Be proactive.
- Be able to write scientific reports and articles.
- Enjoy supervising students in L3, M1 and M2.

Work Context

The candidate will be based at LTeN, which is hosted by Polytech'Nantes. He/she will join LTeN's MIRYADE theme, led by Benoit Rousseau, coordinator of ANR ORCHESTRA. Within MIRYADE, the candidate will interact with Abdérezak Aouali, Junior Lecturer. There will be regular interaction with GeM, which is based at Centrale Nantes. Both units are part of the Science and Technology Division of Nantes University. The candidate will work in a dynamic scientific environment within a European metropolis, combining cultural, environmental and human development. Access to Paris by High-speed train in 2 hours and to the Atlantic Ocean in 45 minutes. The expected monthly remuneration is €2,840 gross, with a possible start date of 1 March 2026.