Research And Analysis On Performance Of A New Solar Thermal Collector

Owing to the energy crisis and air pollution becoming more and more serious, the energy structure based on conventional energy would fail to catch up with the needs of the development gradually. It has become our common view to accelerate the development and to utilize of solar energy as the main body of the renewable energy. But solar energy is the low grade energy, it must implement the gather of solar energy to achieve the feasibility and economy of energy utilization in order to get the high grade energy. In the field of solar energy utilization, improving the conversion efficiency of photovoltaic/thermal and reducing cost have profound significance to promote the development of the solar industry. On the basis of a lot of reading related literatures, this paper puts forward a new type of multi-facet concentrator, which can meet the need of middle-temperature solar.Firstly, this paper analyzes the physical model and mathematical model of multi-facet concentrator, which has a number of small rectangular plane mirror installed parabolic structure framework. Using geometry theory and the Monte Carlo method study its’geometric optical characteristics and focal plane density distribution, and consider influence of different error on geometric concentrating ratio and the flux density distribution. Research results show that:compared with the traditional disc type condenser, the new type of multi-facet concentrator increase the focal plane of the light spot area and uniform the energy flow density distribution; The geometric concentrating ratio of multi-facet concentrator can meet the using demand of the medium temperature field; with the same external conditions, its performance affected by comprehensive error is smaller than traditional dish concentrator.Secondly, the performance of cavity postures solar receiver is studied. According to flux density distribution of the focal plane, combined with a large number of relevant literatures of cavity structure, the hemispherical receiver and cylindrical receiver are mainly studied. Structure parameters on the energy flow density distribution are also analyzed. According to the energy flow density uniformity index and the practical application of the needs of the receivers, the shape and structure parameters can be selected.Finally, selecting cylindrical receiver as the research object, the energy loss and the average temperature of the fluid is analyzed. It focus on the research of the pipe diameter, emphasized on the research angle and the height of the cylinder of the receiver’s influence on the energy loss. It obtains the influence factors on the average temperature of the fluid affects compared the experimental research of others.