CFD Analysis of the Use of Desert Sand as Thermal Energy Storage Medium in a Solar Powered Fluidised Bed Harvesting Unit

Abstract

Abstract This work presents an Euler-Euler hydrodynamic and heat transfer numerical analysis of the multiphase flow involving desert sand and a continuous gas phase in a compact-size fluidised bed. The latter is part of a novel conceptual solar power design intended for domestic use. Desert sand is a highly available and unused resource with suitable thermal properties to be employed as thermal energy storage medium. It also allows for high working temperatures owing to its high resistance to agglomeration. Computational Fluid Dynamics simulations are used here to assess the heat transfer between desert sand and several proposed working fluids (including air, argon, nitrogen and carbon dioxide) to justify the design in terms of equipment dimensions and suitability of the materials used. The results show that the device can provide up to 1,031 kW when using carbon dioxide as the heat transfer fluid.