Performance analysis of a novel liquid desiccant-vapor compression hybrid air-conditioning system

LDCH (Liquid desiccant-vapor compression hybrid) air-conditioning systems are popular for reducing energy consumption. This work tests a conventional LDCH air-conditioning experimental setup and establishes the corresponding mathematical model to analyze the effect of the concentrated solution branch in the SSHE (solution-solution heat exchanger) on the cooling capacity of the evaporator; the results show that the percentage of cooling capacity loss of the evaporator exceeds 10% with the small concentration difference of 1.5% in the conventional LDCH air-conditioning system. Afterwards, a new LDCH air-conditioning system is proposed by adopting an auxiliary regenerator to cut down the cooling capacity loss of the evaporator, and the analysis results show that there is a big temperature drop of the concentrated solution branch after being pretreated by the auxiliary regenerator; under the condition of concentration difference of 2.65%, the inlet temperature of concentrated solution branch from the regeneration side in the SSHE can decrease over 6 °C; and the extra heat load entering the dehumidification side from the regeneration side obviously decreases. Consequently, the evaporator only needs to spend 1.5% of its cooling capacity on the compensation for the extra heat load.