The influence of heat exchanger parameters on the optimum cycle time of adsorption chillers

The research investigated the influences of heat exchanger parameters, such as heat capacity and NTU, on the optimum performance of a single-stage adsorption chiller. Silica gel-water pair was chosen as the adsorbent-adsorbate combination so that low temperature heat source under than 100 degrees C could be utilized as the driving force. The mathematical model of the adsorption chiller using dimensionless parameters was developed and a global optimization method called the particle swarm optimization was applied in the simulation to obtain the optimum cycle time. The results showed that the smaller heat capacity heat exchanger improved both the maximum specific cooling capacity (SCC) and the COP. While, the larger NTU of the adsorbent bed resulted in the decrease of the COP due to the short cycle time although the maximum SCC was enhanced. (c) 2009 Elsevier Ltd. All rights reserved.