Performance analysis of solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city

Due to the absence of cooling tower and independent on water, the air cooled solar double effect LiBr/H2O absorption cooling system is more convenient to be used in commercial building and household use. The performance with collector temperature is an important field for such system. The paper mainly deals with the performance with collector temperature for the solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city. The parameters of system are: aperture area of collector array is 27 m2, tilted angle of collector with respect to the horizontal plane is 20 toward to south evaporator temperature is 5 °C and the cooling capacity is 20 kW. The simulation is based on the meteorological data of monthly typical day which was summarized from a year round measured data. A corresponding parametric model was developed. The hourly and average performance with the collector temperature for monthly typical day was obtained and discussed. It was found that the suitable working range of inlet temperature of collector is 110-130 °C to improve performance and lower the risk of crystallization. The difference of hourly total efficiency in 9:00-16:00 is less, and the monthly total efficiency from May to October is approximate. The yearly performance of system including total efficiency, cooling capacity per area of collector and solar fraction was given. Furthermore, the effect of effectiveness of heat exchanger and pressure drop on total efficiency and solar fraction was studied and compared. The paper can serve as a preliminary investigation of solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city, and provides the foundation of further study.