Performance Analysis Of Solar Absorption Refrigeration System Driven By The CPC As The Heat Source

In the past more than two centuries, fossil-fuel-based energy system as an important material foundation plays an extremely important role in promoting the development of human society. However, the human excessive exploitation of conventional energy to the earth resulted in serious consequences, such as the deteriorating environment and the imminent exhaustion of resources. Therefore, as quickly as possible to explore a kind of safe, clean, renewable energy system has become an important issue that must be addressed for the human being.Solar energy is one of the world’s most abundant renewable energy. Solar with no damage and pollution to the ecological environment, widely distributed, access to convenient without exploration, mining, transportation, and other characteristics get increasingly subject to human attention. With the continuous progress of science and technology, the use of solar thermal technology has been greatly developed.Solar refrigeration-air conditioning as a new energy-saving air-conditioning system in the modern building, because of its energy use to match with the season, no environmental pollution and other advantages get attention by the scientific community. But the technology is due to the influence of the collector efficiency is not high, covers an area of tracking difficulties, unable to meet the requirements of high-performance chillers high heat source, can’t guarantee the high efficiency of refrigeration, yet wide application. On the basis of comprehensive analysis, the choice of a better solution to the above problems compound parabolic collector, high efficiency and refrigeration, combined with good stability double effect lithium bromide absorption chiller system works, performance, and economic research and analysis.On the basis of a comprehensive analysis of the optical principle of the CPC solar collector and its constituent parts:intermediate absorbing body, the technical requirements of the reflector with transparent bezel, structural characteristics and material properties and other characteristics physical and mathematical model of the heat transfer process. Through simulation shows that:the cross section of the CPC collector temperature distribution is more uniform, a higher temperature of the vicinity of the intermediate absorbent body, can play an ideal collector effect. CPC solar collector outlet temperature is increased with increasing solar radiation intensity decrease with the increase in the inlet velocity, At the same time increase with the length of the tube, in the middle of the CPC solar collector receives outer wall temperature the transparent bezel temperature, the CPC reflector body wall temperature will gradually larger, the transparent baffle and CPC reflector body wall temperature growth of smaller, while the coating absorbing coating in the middle of the temperature of the receiving body with the tube length becomes greatly increased significantly.The article also uses the relationship between mass balance and energy balance to establish steady-state mathematical model of the hot water double effect lithium bromide absorption chiller. By calculation, get the initial design parameters, including the system of the heat exchanger heat transfer area, including the contents of the heat source water inlet temperature and flow, the cooling water inlet temperature and flow, the temperature of the chilled water outlet flow. As a basis of it. the article gives the system simulation and analysis.The analysis pointed out that the cooling capacity and COP of the system becomes large as the inlet temperature of the heat source water elevated. Heat source water inlet temperature rises to10℃, the amount of the refrigerant of the system be increased by approximately11.3%. Heat source water flow changes similar to the impact on the system COP and cooling capacity, the flow is low, the system COP and cooling capacity increases obviously, but when the flow is fast,the system COP and cooling capacity becomes slower. Chilled water outlet temperature will in the system cooling capacity and COP becomes large, but too low outlet temperature easy to cause the evaporator water freezing of frozen or cold agent, the chilled water flow rate will cause the system increased cooling capacity and COP becomes large, but the amplitude is very small. The cooling capacity and COP of the system decreases with the rise of the cooling water inlet temperature, increases with the increase of the cooling water flow rate, but relatively speaking amplitude are relatively slow. Through simulation prove that CPC collector as the solar cooling system to have efficient collector performance as driving heat source, it is as much as possible to raise the temperature of the heat source water to an appropriate range to ensure the efficient operation of the refrigeration system.In addition, this paper surveys the climatic conditions of Jinan City in Shandong province which belongs to the third of the five solar radiation regions. Through researching the sun radiation and the monthly amount of radiation and analyzing the feasibility of promotion, the results showed that the higher amount of radiation in Jinan City, and more uniform, suitable for development, the use of solar energy related equipment.Finally, we choose a three stars hostel of Jinan City, for instance, to do the energy analysis and economic comparison of CPC solar absorption refrigeration system with conventional direct-fired absorption refrigeration system. Analysis results show that the CPC solar absorption refrigeration system has a large initial investment, but has the day maintenance of very low running costs. The initial investment of Conventional direct-fired refrigeration system is not high, but the amount of day-to-day use of electricity and gas is high. For example, the annual running costs of cooling in summer only up to282,300Yuan. Through net present value algorithm, the CPC solar absorption refrigeration system, compared with the ordinary direct-fired air-conditioning system, the annual operation and maintenance cost savings of228,900Yuan, about8.15years to recover investment.