Advanced performance of an open desiccant cycle with internal evaporative cooling

• An evaporatively cooled sorptive coated heat exchanger was experimentally tested.
• The evaporatively cooled process outperforms the air cooled adsorption process.
• Adsorbed water mass was increased by 46% and cooling capacity by a factor of 4.1.
• Earlier research of air cooled adsorption was analysed with a dynamic model.
• In comparison the evaporatively cooled prototype shows an enhanced performance.

An enhanced evaporatively cooled open sorption cycle which can be driven by solar thermal heat is presented as an environmentally benign alternative to conventional air conditioning cycles. Experimental data of the core component – the desiccant coated heat exchanger – cooled by water evaporation are given. This evaporation of water in the heat exchanger leads to an increase in adsorbed water mass by 46% and an enhancement of the cooling capacity by factor 4.1 when compared to a solely air cooled process. By simulation analysis, the recently designed heat exchanger is then compared to data of an air cooled open sorption process published in earlier research. Measurement data of this earlier research are analysed with a dynamic model. It is demonstrated that only a fraction of the dry desiccant mass was actively cycled in the earlier prototype. Simulation of the evaporatively cooled current prototype underlines the enhanced performance that can be achieved with the new concept and prototype design.