| With the improvement of the standard of living, air-conditioner has been more and more popularized. At the same time, mechanical compression refrigerators consume a big quantity of electric power and indirectly make the pollution problem severe, which bring forward a great challenge to the human's sustainable development. Among the various solutions, the utilization of solar energy and other regenerative energy for refrigeration is one of the promising choices. Because of its ability to utilize the low-temperature thermal energy resources, and its simple structure and reliable operation, the ejector refrigeration system has gained much attention.In this paper, the study of the performance and characteristics of the solar ejector refrigeration system and its key component, the ejector, is carried out, which is aimed to solve some chief technical problems. An ejector refrigeration experimental set was designed and built. And a new solar bi-ejector refrigeration system was worked out. The following are the main contents:1. Based on the one dimensional performance analyzing and structure designing method and the achievement of the Dalian University of Technology, a package of software for the performance predicting and structure designing was made. The relationship between the operation condition and the ejector performance and the designing structure was studied.2. Through solving the two-dimension axial-symmetry flow model, the relationship between the flow field and the performance of the ejector was studied. An experiment set was built to prove the accuracy of the model. The relationship between the operation conditions and the flow field was studied. The flow filed and the performance at different ejector structure was studied.3. The performance of several refrigerants and the thermal storage of the solar ejector refrigeration system were studied. According to the solar radiation data of a city in north China, the simulation of the performance of a solar ejector refrigeration system was carried out, in which R123 was taken as the refrigerant. The operation result showed that with a solar collector of 20 square-meter, the cooling capacity of the solar ejector refrigeration system could meet the demand of a living house of 60 to 70 square-meter (when the booster was present) or of 20 to 30 square-meter (when the booster was absent) from 10am to 4 pm. The maximum cooling capacity was 1.8kW with COP of 0.259 when the booster was absent, or the maximum cooling capacity was 5.2kW with COP of 0.777 when the booster was present.4. An experiment set of solar ejector refrigeration system was built, in order to study its performance characteristics and the key influence factors, in which R123 was taken as the refrigerant. Through regulation of the heater power, the solar radiation varying with the time was simulated. The collector was 10 square meter. The refrigeration system could provide the cooling water of 15℃, the system COP was 0.20, the maximum cooling capacity was 0.4kW.5. After study of working principle and performance of the vapor-liquid ejector, based on its important character that its discharged pressure can exceed the pressure of the working vapor, a new bi-ejector refrigeration system was designed, in which the mechanical pumpis replaced by a vapor-liquid ejector. The performance of the vapor-liquid ejector and the feasibility of the new bi-ejector refrigeration system were studied. Although the simulation results show that compared with the solar ejector refrigeration system the solar bi-ejector refrigeration system loses 20% COP, it consumes no electricity power and has no mechanical component.
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