Thermal energy storage is a solution to increase efficiency, reduce the required power and/or improve the integration into smart grids of energy systems. The intensification of storage systems requires the use of phase change materials (PCMs). These PCMs rarely have good conductivities which hinders the performance of the storage system (low power). To solve this problem, we propose to work with composite assemblies of PCM incorporated in a conductive matrix. Expanded Natural Graphite (ENG) is a good candidate to act as a conductive matrix. The desired storage temperature will be the determining criterion for the choice of PCM (oil, paraffin, sugar, salt, etc.).
This storage technology, for temperatures between 40 ° C and 120 ° C, has already been explored by our teams. We are now looking to explore the feasibility of storing heat at a lower temperature (-15 ° C to 0 ° C) for refrigeration or air conditioning applications. Mixtures of water and antifreeze seem to be good PCMs.
The objective of the project is to realize an experimental storage system composed of an ENG plate bathed in a tank filled with a mixture of water and antifreeze. This system will make it possible to experimentally quantify the performance that can be obtained with these materials. It will also make it possible to identify possible scientific obstacles that the use of this technology could generate (supercooling, delamination by expansion, etc.).
The candidate should have good skills for reading scientific articles and for experimentation, have analytical, writing and communication skills (in French or English). Knowledge of heat transfer would be an asset. Excellent interpersonal skills, thoroughness and a good ability to work in a team are expected. The student will carry out his / her activities at the Icam Nantes campus