Hybrid liquid desiccant air-conditioning system: Experiments and simulations

This study focuses on a hybrid liquid desiccant air-conditioning system consisting of a conventional liquid desiccant system and a vapour compression heat pump. The hybrid liquid desiccant air-conditioning system is expected to enhance the system efficiency of a conventional liquid desiccant system. In this study, the liquid desiccant is aqueous solution of lithium chloride and the refrigerant of the vapour compression heat pump is R407C. The main feature of this system is that the absorber and regenerator are integrated with the evaporator and condenser respectively. The performance evaluation test is conducted to obtain the primary data. Additionally, the improvement method for the system efficiency is discussed by the mathematical calculations. As a result, the system can dehumidify 5.9 g/kg(DA) under the conditions of summer in Tokyo, Japan. Then, the calculation results show that COPs can become higher by improving the compressor isentropic efficiency and the temperature efficiency of solution heat exchanger. ► We focus on a hybrid liquid desiccant air-conditioning system. ► The feature of the system is that the absorber is integrated with the evaporator. ► We develop a mathematical model considering heat and mass transfer in the absorber. ► The simulation and experiment are carried out to reveal the system performance. ► COP becomes higher by improving the compressor and the solution heat exchanger.