Performance enhancement of adsorption beds with silica-gel particles packed in aluminum foams
Abstract Effective thermal conductivity of a silica-gel/water adsorption packed bed is significantly enhanced by placing silica-gel particles in a high-porosity aluminum foam. The enhancement leads to several folds increase in the specific cooling power (SCP), cooling capacity per unit volume (CPv) and coefficient of performance (COP) of an adsorption cooling (AD) chiller. The thermal response and adsorption kinetics of various silica-gel/aluminum foam beds under typical operating conditions are investigated experimentally and numerically. Effect of pores per inch (PPI) of the foam, silica-gel particle size, bed height and adsorption isotherm of different types of silica-gel on the bed performance are investigated. Based on the results, aluminum foam with 20 PPI is recommended for adsorption cooling applications due to its high surface area and small cell size. 20 PPI aluminum foam can deliver a SCP of 827 W/kg, a CPv of 517 W/m3 and a COP of 0.75.