Design of a Latent Thermal Energy Storage System Using Ice and Roll-Bond Heat Exchangers

This work is developed in the framework of the EU project AGRI-COOL, which aims at deploying innovative off-grid cold rooms in Africa. The core of the system is a latent heat thermal energy storage (LTES) system which uses ice as phase change material and the roll-bond heat exchangers. The LTES is designed to store energy during the daily hours, when an excess of electricity is produced by a suitable solar array that powers a chiller also used to refrigerate the positive cold room. During the night, when the solar system does not work, the LTES supplies the cooling load. Two different tank configurations were investigated: rectangular and cylindrical to understand the effects on the layout on the performance of the LTES. A numerical framework is developed using ANSYS Fluent. The roll- bond HXs are modelled as isothermal 7lat plates with different sizes. The effects of the roll- bond HXs layout is also studied to identify the best performance of the system in terms of lower solidification time and volume allocation. The results are shown in terms of temperature, liquid fraction, energy storage density, and solidification time.