Parameter Optimization Of Solar-assisted Liquid Desiccant Cooling System: A case study in Hong Kong

摘要

By using a liquid desiccant ventilation system for dehumidification and an air-handling unit for cooling, theliquid desiccant cooling system (LDCS) system became a promising alternative for traditional technology.Solar thermal energy is suitable to deal with the heat requirement of LDCS in buildings, especially in the areaswith abundant solar radiation. The energy saving of solar-assisted liquid desiccant air-conditioning system issignificantly affected by various operation conditions, and multi-parameter optimization was necessary toimprove the system applicability. In this paper, we investigated the impact of five main parameters on thesystem performance via self-developed system modelling, including the solution mass flow rate, concentration,cooling tower flow rate, and solar water flow rate and installation area of solar collector. A typical commercialbuilding in Hong Kong was selected as a case study, which air-conditioning load was obtained by Energyplus.The results indicated that the installation area of solar collector showed the greatest impact, and the effectof heating water flow rate was also important. The effect of desiccant flow rate was significant, but theinfluence of solution concentration was slight. Then, the multi-parameter optimization was conducted forobtaining a maximum annual electricity saving rate based on the Multi-Population Genetic Algorithm. Theoptimized installation area of solar collector was 72 m~2, and the heating water flow rate was 0.66 kg/s. Theoptimized solution flow rate was 0.17 kg/s. The required cooling water flow rate was around 0.8 kg/s.