Study On Fresnel Solar Collector With Rectangular Cavity Receiver And Application Of Single/Double Effect Absorption Solar Cooling System

Two kinds of Fresnel solar collector with rectangular caivity receiver were investigated in this paper.The Linear Fresnel Reflector solar collector which was one of the two was applicated to drive the single/double effect absorption solar cooling system.It was also studied theoretically and validated by experiments.The specific works of this thesis are as follows:1.The theoretical analysis was set up based on the solar collector with cavity receiver to investigate the heat transfer process.The law of heat transfer,combined with the energy transfer methods were employed to evaluate the performance of the solar collector.2.The theoretical analysis and experimental research of the Linear Fresnel Reflector(LFR)solar collector were set up in the thesis.The system optical performance was simulated.The factors which influenced the optical efficiency were investigated and optimized.The performance of the solar collector was simulated and validated by the experiments.The factors which influenced the thermal efficiency were analyzed.For the LFR solar collector,the pure optical efficiency is 78.5%and the highest temperature is 180~oC.Form 80~oC-150~oC,the thermal efficiency varied from 52.3%to 32.6%,and overall heat loss coefficient varied from 10.8W/m~2 K to 21.2 W/m~2 K.3.The theoretical analysis and experimental research of the novel beam down solar collector with Fresnel heliostats and cavity receiver were set up in the thesis.The system optical performance was simulated.The factors which influenced the optical efficiency were investigated and optimized.The performance of the solar collector was simulated and validated by the experiments.For the novel beam down solar collector with Fresnel heliostats and cavity receiver,form 100~oC-160~oC,the thermal efficiency varied from 51.6%to 33.2%,and overall heat loss coefficient varied from 7.6 W/m~2 K to 16.8 W/m~2 K.4.The performance of the single/double effect absorption chiller driven by LFR solar collector was studied both theoretically and experimentally.For the absorption chiller,the operating mode automatically changed as the variation of hot water inlet temperature.As the hot water inlet temperature was higher than 85~oC,it's operating under single effect,the cooling capacity is 90kW and the COP is 0.7.As the hot water inlet temperature was higher than 145~oC,it's operating under double effect,the cooling capacity is 130kW and the COP is 1.2.Meanwhile,the study about generation temperature and cooling temperature were also investigated to obtain the influence for the chiller.5.The single/double effect absorption solar cooling system driven by LFR solar collector was investigated through simulation and experiments.This solar hybrid cooling system is designed for operating with different modes under various solar irradiances and requirements of load.For the typical summer condition,the solar hybrid cooling system will be available for a whole day,the chiller can operate under double effect mode for about2-3hours and the average COP of the chiller can reach up to 0.88.Compared with the conventional solar cooling system,this system has a longer cooling time and higher energy transfer efficiency.