Effect of storage medium on thermal properties of packed beds

✍ Scribed by S.L. Aly; A.I. El-Sharkawy

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 571 KB
• Volume: 10
• Category: Article
• ISSN: 0890-4332
• DOI: 10.1016/0890-4332(90)90201-t

✦ Synopsis

Al~traet--The present paper is concerned with studying the effects of storage medium propert/es on the thermal behaviour of packed beds during charging. A transient onc-dimomionai two-pha~ model is used to describe the temperature fields in the air and solid media constituting the bed. The numerical solution of the resulting two-coupled partial differential equations is obtained, and the variation of thermal energy stored with time is computed. Solutions are obtained for a wide range of storage media (the mild phase) properties, namely density, thermal conductivity and specific heat. The results show that increasing either the density or specific heat increases the rate and capacity of energy storage, and decreases the rate of temperature rise throughout the storage medium. On the other hand, increasing the thermal conductivity is found to markedly increase the rate of temperature rise and energy stored inside the bed up to a certain time during charging, beyond which this trend completely reverses. In addition, the thermal storage properties of aluminum, steel and rock-packed beds are computed and compared.