Analysis and optimization of the closed-adsorption heat storage bed performance

Sorption heat storage attracts considerable attention because its relatively high theoretical energy density compared to other heat storage methods offers various opportunities in the design of renewable and sustainable energy systems. However, limited heat transfer in the material bed remains one of the main limitations of a successful introduction to the market. In the present study, a mathematical model of the heat and mass transfer processes inside an adsorption bed of silica gel embedded with cylindrical and rectangular fins has been developed. A systematic analysis has been conducted to augment thermal transport in the adsorption bed with rectangular and pin fin configurations. A parametric study has been conducted for both fin configurations at different bed heights (δb), fin diameters/thicknesses (ϕfin/δfin) and fin spacings (δs). Further, a design-of-experiments study is conducted to relate the energy discharge (Edis) and peak power (Wpeak) to the various governing parameters, as such identifying which parameters maximize energy discharge (Edis) and peak power (Wpeak). The design-of-experiment study reveals that the rectangular fin configuration shows better performance compared to the cylindrical fin configuration.