Experimental and numerical investigations of an adsorption water-zeolite heat storage for refrigeration applications. (October 2017) - Semprini, Simone
Abstract: A zeolite 13XBF - water adsorption heat storage for refrigeration purposes is presented in this paper. The system comprises a reactor, in which the adsorption process takes place, and a condenser/evaporator unit. The aim is to be able to recover waste heat, excess solar heat or off-peak electricity (electricity-to-heat), to store it with minor losses and to use the available energy when it is needed, either for cooling and/or for heating. A prototype of the system has been developed and tested. The studied configuration is designed to recover heat from air flows (at up to 300 °C) and to produce cooling of the indoor ambient air (range 12-20°C). The reactor includes only one bed and the entire system is designed to store energy (3 kWh) to provide the desired cooling effect for several hours. Moreover, the heat and mass transfer has been numerically simulated with a CFD software. A 2D model of the sorption storage and a 0D model for the condenser/evaporator unit have been coupled. The experimental results showed that the concept is suitable for the application, but some challenges still exists: heat transfer inside the adsorber (i) and vacuum tightness of the system (ii). The results of the simulation are consistent with the ones from the experiments, demonstrating the suitability of the theoretical model.