Missions

In collaboration with a team at CEA le Ripault, the OR2T "Optics, Thermal Radiation and Transport" team of the CEMHTI-CNRS laboratory (UPR 3079) is recruiting a researcher (M/F) in the field of materials for high-temperature applications, to optimize their radiative properties at high temperatures.

Activities

The project is a collaboration between the CEMHTI laboratory and CEA Le Ripault.

The "digital materials" approach initiated by CEA Le Ripault and CEMHTI some fifteen years ago aims to optimize the performance of new materials by simulating coupled conducto-radiative heat transfer in heterogeneous media. During this period, they have led to the establishment of two joint theses on this theme. The search for possible innovations focuses on high-temperature applications (> 1000°C), and in particular on the design of thermally insulating architectural materials. These "digital materials" approaches should help us to design materials whose performance, evaluated by digital experiments, can be optimized according to the nature of the basic constituents we choose and the microstructure we generate digitally.

For these approaches to be predictive, it is therefore necessary to determine the optical and thermal properties of heterogeneous materials and their basic constituents at high temperatures. Acquiring these properties is essential, as they form part of the data required for (i) homogenization models to aid material design, and (ii) material validation. To achieve this, complementary experimental resources and theoretical approaches have been set up at CEA Le Ripault and CEMHTI.

The aim of this new collaboration is to continue the work already underway to develop a complete chain for optimizing the design of innovative materials, enabling their behavior under high-temperature thermal stress (or high heat flux) to be assessed. This work will be based on existing numerical and experimental tools contributed by each partner.

The activities of the person recruited will be :
- Characterize the optical and radiative properties (spectral emissivity) of opacified fibrous media at high temperatures (> 1000°C).
- Extract the optical indices of these materials using these spectral measurements, a code for generating digital materials and a code for simulating radiative transfer using an MCRT technique within digital materials.
- Develop these two existing numerical tools and adapt them to the new materials studied (with opacifiers).

- Characterize the high-temperature thermal performance of these fibrous media on CEA's ECOTHERM bench.
- Simulate the coupled conducto-radiative transfer within these media, using CEA's THERMIVOX calculation code.
- Validate numerical models (simulation/experimental comparison).

- research innovative material architectures using these tools to optimize high-temperature thermal performance (texture, nature of solid phases and their volume fractions).

- Process and interpret data.
- Promote results through publications and participation in conferences.
- Write reports, technical documents and scientific publications.
- Ensure skills transfer between CEMHTI and CEA Tours.

Skills

- A PhD in materials science in the field of modelling the physical properties, in particular thermal and/or optical properties, of heterogeneous materials is required.
- Programming skills and experience (C++ or Python) are essential.
- The candidate must have experience in experimental measurements of the properties of materials at temperature and, if possible, experience in infrared spectroscopy of materials at temperature.
- Fluency in reading, writing and speaking English to participate actively in project dissemination activities.
- Organizational skills. The candidate is expected to initiate, plan, implement and deliver research results within defined deadlines.
- Proficiency in the use of IT tools for equipment control, data processing and analysis.
- Respect health and safety rules related to the field.
- Ability to work while respecting the confidentiality of research work and results.

Deadline for application : 16/10/2024

Work Context

The researcher will be based at the laboratory's high-temperature site, where he/she will join the "Optics, Thermal Radiation and Transport" team, and may be required to travel to the CEA Le Ripault site.