Design, construction and experimental performance of a chemisorption chiller driven by hot water
Rogério Gomes de Oliveira1; Daniel João Generoso2; Bruno Rocha Colonetti1; Patrick Nikson Rubbo1
1 Universidade Federal de Santa Catarina; 2 Instituto Federal de Santa Catarina
doi:10.20906/CPS/COB-2015-2621
Resumo
We designed, constructed and tested the performance of a chemisorption chiller in which hot water was the main source of energy. It had one evaporator, one condenser, two reactors, and used ammonia as refrigerant. Each reactor contained 9.4 kg of composite consolidated adsorbent with 60 % (w/w) of NaBr and 40 % (w/w) of expanded graphite. The mass flow and temperature of water at the inlet and outlet of the condenser, evaporator and reactors were measured to allow the calculation of the global heat transfer coefficient of the condenser and evaporator, and the chiller cooling power and coefficient of performance (COP). The values of the calculated global coefficient of performance were compared to those obtained by Nusselt correlations available in the literature. The experiments to obtain the chiller's performance were conducted using hot water at 70 °C as main heat source, tap water with temperature of 28 °C as heat sink, while the inlet temperature of water in the evaporator was being reduced from 23 °C to 4 °C. With the reduction of the water temperature that flowed through the evaporator, the mean cooling power and COP also decreased, and from the end of the first cycle to the end of the last one, their values dropped respectively, from 1690 to 710 W, and from 0.41 to 0.19.
Palavras-chave: Chiller; Adsorption; Ammonia; Air conditioning