Investigation on the thermal energy storage characteristics in a spouted bed based on different nozzle numbers

Abstract

This paper presents the results of the simulations of the thermal storage and thermal release processes in a spouted bed using a self-developed computational fluid dynamics–discrete element method (CFD–DEM) model to analyze the thermal energy storage (TES) characteristics of the spouted bed with varying nozzle numbers. The thermal storage capacity, thermal release capacity and thermal storage efficiency were analyzed. Additionally, the effects of gas inlet jet number and gas flowrate on the thermal storage characteristics are discussed. The results showed that a higher number of nozzles resulted in a faster change of particle temperature, higher gas phase temperature field update rate and a higher thermal storage capacity. However, when the number of nozzles is increased from 1 to 2 and then 3, the rate of increase in total thermal storage and total thermal release decreases, and the increase in thermal release is always higher than the increase in thermal storage. When the number of nozzles is increased from one through three, the thermal efficiency increased from 52.9% to 75.6%, establishing that a higher number of nozzles improves the thermal efficiency.