Thermal conductivity of selective water sorbents under the working conditions of a sorption chiller

This paper presents the experimental data on the thermal conductivity of the composite sorbents, CaCl2/ SiO2 and LiBr/SiO2, measured by the "hot wire method" under various conditions of vapour pressure P-H2O, temperature T and water uptake w. The measurement ranges were chosen according to the operating conditions of a typical sorption cooling cycle (10 < P-H2O < 70 mbar, 40 < T < 130 degreesC). The obtained results show that the sorbent thermal conductivity lambda(T, P-H2O, w) increases considerably as the uptake of sorbate rises, while its dependence on pressure and temperature is; in the studied range, almost negligible. Finally, the influence of thermal conductivity on the specific-power of the sorption chiller is discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.