Experimental study of a solar adsorption refrigeration system integrated with a compound parabolic concentrator based on an enhanced mass transfer cycle in Kunming, China

A new solar adsorption refrigeration system integrated with a compound parabolic concentrator (CPC) adsorber was proposed. Comparative experiments were conducted to investigate the system behaviour with the enhanced and natural mass transfer cycle under different weather conditions in Kunming, China. The parameter lambda (the refrigerant utilization ratio) was defined to describe and compare the effective utilization ratio of the refrigerant in a refrigeration cycle for some different adsorption refrigeration system with a different quantity of the adsorbent and refrigerant. The results show that the system performance level with the enhanced mass transfer cycle is always higher than the system performance level with the natural mass transfer cycle under different weather conditions. On sunny day with a clear sky, the volume of the desorbed refrigerant and the COPsolar with the enhanced mass transfer cycle were increased by 39.2% and 39.0%, respectively, compared with the natural mass transfer cycle. The refrigerant utilization ratio in the CPC adsorption refrigeration system could be improved by 32.5% and 51.2% for the natural and enhanced mass transfer cycle compared with the non-CPC adsorption refrigeration system, respectively. While on sunny day with a partly cloudy sky, the volume of the desorbed refrigerants and the COPsolar with the enhanced mass transfer cycle were improved by 51.7% and 52.8%, respectively, compared with the natural mass transfer cycle. And the refrigerant utilization ratio in the CPC adsorption refrigeration system improved by 33.5% and 61.2%, respectively, for the natural and enhanced mass transfer cycle compared with the non-CPC adsorption refrigeration system.