A novel dual-wheel air-conditioning system operating strategy in different seasons

Abstract

The application of solid desiccant air-conditioning systems can significantly reduce building energy consumption. Previous studies have focused on innovating the integration of solid desiccant air-conditioning systems (DACS) to improve dehumidification performance in summer. In this paper, a novel DACS is proposed, which can humidify the supply air in winter based on satisfying the dehumidification demands in summer. It can satisfy the year-round humidity requirements of domestic housing with significant savings in humidification costs. Furthermore, the operating strategy of the novel DACS is proposed, particularly for winter humidification conditions. It is adaptable as well as cost-effective compared to traditional operating strategies. The dehumidification/humidification capacity of the core component, polymer desiccant wheel, and the variation of temperature rise/temperature drop are investigated under different variations of parameters, including air temperature, air humidity, air volume flow rate, and wheel speed. The results show that with the increase of supply air mass flow from 0.6 kg/s to 1.9 kg/s, the power consumption of the system only increases by 9.5 kW. In winter, when the supply air temperature decreases from 8 °C to 1 °C, the power consumption increases by 7.2 kW, but in summer, when the temperature of the supply air increases by 7 °C, the power consumption of the system decreases by 7.0 kW. The power consumption of the system varies greatly when the humidity of the supply air is less than 17 g/kg, conversely, the power consumption of the system showed a negative trend. The analysis demonstrates the effective performance of the proposed system under varying climatic conditions.