Experimental Investigation of the Heat Performance Using a Packed Bed of Ceramic Balls for High Temperature Thermal Energy Storage Unit
Abstract
A thermal energy storage (TES) system was designed based on a packed bed of ceramic balls as storage material and air as heat transfer fluid (HTF). A series of contrast experiments were carried out under specified working conditions to analyze the heat performance of TES unit. The results showed that temperature distribution in axial direction of the packed bed and thickness of thermal stratification can be manually controlled by adjusting the air flow rate or the heating power during charging to achieve a better discharging performance. The packed bed has a good temperature uniformity along the radial direction which means a less exergy loss and smaller convective mixing radially. It was also shown that the TES unit has a highest discharging heat power of 16.5 kW, and discharging efficiency of 90%, indicating that the TES unit can achieve to store and release heat effectively.
Keywords
Packed bed, Thermal storage, Sensible heat, Air, Ceramic balls