In INDHEAP project, CEA is responsible of all tasks related to the thermal energy storage, which include the development of a prototype of so-called “dual thermocline thermal energy storage” to be installed on an industrial site of one of project’s partner. This technology of thermal storage is based on the storage of heat into granular bed of solid material such as rocks. The postdoctoral position is focused on the thermomechanical behaviour of the granular bed and its interaction with the storage’s tank. The proposed postdoctoral position is in the continuation of related works already performed by the CEA for hydrogen and thermal storages, and in particular the PhD thesis of Nahia Sassine (Université Grenoble Alpes, 2018).

The proposed study is in the line with the so-called “thermal ratcheting” phenomenon, i.e. the accumulation of thermal stress in the tank of a granular bed under thermal cycling. Up to now, there is no easy way to estimate this wall stress accumulation, and thus, no easy way to calculate it. The ESPERA experimental installation developed during the PhD thesis of Nahia Sassine will be used to characterized this stress accumulation in specific conditions. Main objectives are to obtain relevant experimental data, provide relevant design and manufacturing guidelines and exchange with APAVE-like certification body. Comparison of experimental data with Discrete Elements Method simulation is also considered.

The candidate will notably work on:

· The definition the realization of test campaigns on the ESPERA installation;

· The analysis of the experimental data;

· Numerical work, and notably with Discrete Elements Method (DEM);

· Recommendations and guidelines for design and manufacturing of tank with granular bed under thermal cycling;

· Interaction with APAVE-like certification body

Technical skills :

- Background in mechanics;

- Experience in DEM simulation would be appreciated but is not mandatory;

- Experience and interest in experimental work;

- Background in heat transfer, hydraulic and thermal systems would be appreciated

Human skills :

- Interest for energetic and environmental questions ;

-  Team spirit and adaptability;

-  Scientific rigour;

-  Writing and oral skills

Profile :

-  PhD with mechanics and energetics backgrounds, you have experience in experimentation, conducting tests, analysis and numerical modelling

- English: reading, writing and speaking (mandatory).