Dynamic simulation of a solar desiccant cooling system combined with a ground source heat exchanger in humid climates. (March 2020) - Heidarinejad, Ghassem
Abstract: Buildings share a large amount of total energy consumption in the world, particularly in humid regions, where due to the total consumed energy and environmental issues, desiccant cooling systems have been proposed as an alternative to conventional vapor compression refrigeration systems. The present research investigated the dynamic operation of a solar desiccant cooling system coupled with a ground source heat exchanger (GSHE). Solar energy and GSHE were used as a heat source for regenerating the desiccant and a pre-cooling component, respectively. Simulations were conducted in hot-humid and moderate-humid climates. In hot-humid regions, the aim was to investigate the system operation, while the required regeneration temperatures were controlled to be below a maximum value. In moderate-humid regions, the objective was to regenerate the desiccant wheel entirely by solar energy. The effect of GSHE was evaluated on the provided thermal comfort. Moreover, the impact of desiccant wheel performance and the maximum regeneration temperature was assessed on the dehumidification of the desiccant wheel, system COP, established thermal comfort, and the solar fraction (SF). Results reveal that GSHE dramatically increased the achieved thermal comfort in both climatic conditions. Reduction in the desiccant wheel performance reduced the system COP and provided thermal comfort and daily-averaged SF. The decline in the maximum regeneration temperature decreased the established thermal comfort, but increased the system COP and daily-averaged SF. Highlights: Solar and ground energies have been simultaneously used in a desiccant system. Desiccant wheel has a notable effect on the time-varying operation of the system. Ground source heat exchanger improves level of thermal comfort provided. Presented system can provide thermal comfort with low regeneration temperatures.