A prototype of a fast cycle adsorption refrigerator utilizing a novel carbon—aluminium laminate

Abstract

A laboratory prototype of a fast cycle adsorption refrigerator is presented: it uses a monolithic carbon-aluminium laminate adsorbent and ammonia refrigerant. The system has a high effective thermal conductivity and density bed and is powered by heat and designed to provide a specific cooling power up to 1 kW/kg adsorbent. There are two generators and each one consists of a tubular stainless steel shell containing a laminate of activated carbon discs and aluminium fins formed in situ. The full unit is designed for a power input up to 10 kW and a cooling power up to 3 kW. Preliminary results of the performance are presented and allow assessment of the intensification of heat transfer within the bed. At specific working conditions (evaporating and condensing temperatures, 7.5 and 32°C respectively; generating temperature, 140°C; half-cycle time, 620 s), the results have demonstrated the intensification of heat transfer within the generator through temperature and pressure profiles during the cycles. With an intrinsic heating power input of about 1.130 kW, the refrigerator produces continuously about 0.500 kW of cooling that corresponds to a specific cooling power of 0.180 kW/kg. The cooling coefficient of performance (COP) is about 0.44.