(535a) Investigation of Fluidized Particles for Use in Thermal Energy Storage and As a Heat Transfer Fluid in a Novel Energy System

Solid particles perform as a heat transfer fluid in novel energy technologies because they enable efficient thermal energy storage, are stable at high temperatures, and are inexpensive. Despite the positive attributes of solid particles, the energy transfer to and from the particles is a key technological challenge that must be overcome before particles can reliably be used in energy systems. In a currently developed energy system, particles flow over hexagonal heater elements and are warmed to high temperatures around 1200°C. The particles are then fed into an insulated silo. When the energy is needed, the particles are fed into a pressurized fluidized bed heat exchanger, where the fluidizing gas is warmed and used to drive a turbine. The current work presented uses discrete element simulations and experiments to investigate how energy is transferred to the particles in the charger, and how energy is extracted from the particles within the fluidized bed. The balance between particle fluidization and the heat transfer efficiency is investigated and the simulation results are compared to experimental data.