| With the deterioration of ecological environment and the increase of natural disasters,the impact on human social economy and life is increasing day by day.At the same time,the consumption of traditional fossil energy also forces people to find more alternative clean energy,and the research and application of new energy has become an increasingly hot topic.The winter heating in the severe cold region of North China consumes a lot of energy,so it is urgent to seek clean heating.Solar energy has been used for thousands of years.It is clean and easy to obtain.The solar collector is the core part of the light and heat collection and transformation.In order to improve the effective utilization rate of solar collector,meet the requirements of energy conservation and environmental protection,this paper will use a flat micro heat pipe solar collector as the research object,the component analysis of the various parts for the composition of its key parameters and establish the mathematical model of the core parts of it-flat micro heat pipe heat transfer performance test analysis,and then a set of micro heat pipe flat plate solar collector in series sets of thermal field measurements.The main research contents are as follows:Based on the analysis of the main factors affecting the performance of flat micro-heat pipe,combined with the use conditions of flat micro-heat pipe in solar collector,an experimental platform for the performance test of flat micro-heat pipe with adjustable application parameters was designed and built.Through experiments,the effects of different ambient temperature,different tilt Angle,different liquid filling rate and different working medium on the performance of flat plate micro heat pipe were compared and analyzed.It is found that the heat transfer performance of45°dip micro heat pipe is better than that of 0°and 90°dip micro heat pipe.The heat transfer performance of the acetone solution micro heat pipe with liquid filling rate of 25% is better than that of the acetone solution micro heat pipe with liquid filling rate of 15% and 35%.The overall heat transfer performance of methanol solution micro heat pipe with 25% liquid filling rate is better than that of acetone and R141 b micro heat pipe at high temperature.The structure and internal operating mechanism of the flat plate solar collector with micro heat pipe are introduced.The mathematical model of heat transfer was established for the influence parameters of the micro-heat pipe solar collector with single glass cover,including the environmental parameters,structural parameters and operating parameters.The theory and method of instantaneous efficiency experimental test of series flat plate solar collector are expounded.The theory and method of the instantaneous efficiency test of the series platesolar collector in the cold region of north China are described.Based on a section of plate solar collector array of microheat pipes in series currently in operation in Changchun,an experimental test platform for heat collection performance was designed.It was found that the instantaneous efficiency of plate solar collector of microheat pipes in series decreased with the increase of the number of series.After three series,the efficiency was lower than 0.3,53% lower than that of the first one.And collector outlet water temperature increases with the increase of the serial number first,when the series is almost not change after more than three,come to a conclusion is in the series collection hot effect after more than three pieces of collector,recommended in the northern cold region,unfavorable to the micro heat pipe flat plate solar collector is designed as a series of three or more forms,provide a reference for energy saving reconstruction and the actual engineering. |
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