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With the rapid development of economic, Energy-saving and environmental protection has become a major issue all over the world. A wide range of people are interested in using of renewable energy sources. Solar ejector refrigeration system is a device which use low-grade renewable energy. The biggest difference between this system and the traditional vapor compression refrigeration system is to use ejector instead of compressor. Ejector has a simple structure, no moving parts, and operation and low maintenance costs. But the ejector entrainment ratio is very low, and the practical applications are very few. So far there is no uniform standard for ejector design. How to improve the ejector entrainment ratio is very important for promoting the use of solar ejector refrigeration system.In this paper, studied how ejector structure and operating conditions affect on ejector, in order to improve the ejector coefficient, and to improve their application of the refrigeration system, and provide a theoretical basis for it’s widely used.This paper is based on Sokolov’s 1-D analysis, assume that mixing is constant pressure, accord to empirical formula, and get the structural design of ejector model. Make programmer by Visual Basic 6.0, and use it to calculate the ejector of a solar house ejector refrigeration system.As the ejector flow is complex, 1-D analysis can not maintain its internal flow field. Take FLUENT software as a platform, simulate ejector which use R134a as the refrigerant, acquired the distribution of pressure, velocity and temperature. At the same time, by the use of numerical simulation of flexibility, repeatability, low-cost characteristics, change working parameters such as the operating fluid pressure, second fluid pressure, mixed fluid pressure, and geometric parameters such as ejector nozzle area ratio, nozzle distance, to calculate ejector coefficient under different situations. Analysis the results, and get the parameters how to affect on the ejector performance.
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