One of the emerging thermal energy storage (TES) technologies being investigated at the Australian National University (ANU) is the tightly packed bed for sensible thermal energy storage. The concept aims at reducing the inventory of sodium, which is hazardous and expensive, and it is divided into four main themes: storage materials selection and testing, computational fluid dynamics (CFD) simulation of candidate structured packed bed configurations, system modelling to allow design optimisation and techno-economic analysis of the concept, and bench-scale experiments to provide proof-of-concept of the proposed technology.
A preliminary screening of materials that are potentially compatible with liquid sodium has been carried out, and samples of the selected materials were obtained from bulk manufacturers for testing, along with industrial pricing. Thermodynamic calculations and initial experimental results (using a customised sealed crucible) showed a promising performance of one of the selected materials (i.e. no reaction with sodium). However, there is a need for further analyses (materials characterizations) following longer run testing to better estimate the lifetime of the storage materials exposed to high temperature liquid sodium.
We aim at answering the following research questions experimentally:
· What is the level of impurities in the sodium after exposure?
· What is the effect of thermal cycling on the compatibility of the selected material?
· What is the effect of materials’ porosity on its durability?
· Interest in materials engineering and characterization
· Desire to learn new experimental methods
· Good communication skills
The following scientific papers are suggested for further study:
· Performance of molten sodium vs. molten salts in a packed bed thermal energy storage, Applied Thermal Engineering 141 (2018) 368–377
· Sensible energy storage options for concentrating solar power plants operating above 600° C, Renewable and Sustainable Energy Reviews 107 (2019) 319-337
Materials characterization, heat transfer liquid, energy storage system