Study On The Radiation Law Of Solar Near Infrared Spectrum In Wuhan Area

Energy is the cornerstone of the development of modern society.China’s traditional fossil energy reserves are limited and the pollution of human living environment is serious.In order to accelerate the adjustment of traditional energy structure,China has vigorously developed the use of clean energy.Solar energy is a non-toxic,harmless and resource-rich clean energy.How to maximize the use of solar energy and realize the green and low-carbon transformation of traditional energy is one of the important directions of current research.The near-infrared band of the solar spectrum accounts for the main part of the total solar radiation,which is widely used in HAVC,satellite remote sensing,detection,industry and other important fields.Therefore,the study of near-infrared solar radiation is of great significance for the efficient use of solar energy.In order to explore the variation characteristics of near-infrared spectral radiation inWuhan area,the long-period(November 2021 to December 2022)real-time test of three near-infrared bands(0.870μm,0.936μm and 1.020μm)solar radiation intensity,total solar radiation intensity and sunshine hours has been carried out by self-built experimental test platform in Wuhan area.Based on the experimental test data,the monthly and seasonal variations of radiation intensity in three near-infrared bands have bee analyzed,and the mathematical calculation models of radiation intensity in three near-infrared bands have been established.In addition,the annual distribution of sunshine hours in Wuhan area has been revealed according to the experimental test.Finally,the near-infrared blackbody radiation function has been combined with the flat plate solar collector to propose the mathematical correlation between near-infrared radiation and the outlet water temperature of the flat plate solar collector.The results show that the near-infrared radiation accumulation of the three bands in Wuhan area shows a single-peak trend with the month,and the annual distribution has obvious seasonal characteristics,which are summer>autumn>spring>winter.The cumulative sunshine hours in Wuhan area show obvious’inverted V’distribution characteristics with the month during the study period,and also show the seasonal characteristics of summer>autumn>spring>winter throughout the year.The results also show that the mathematical calculation model of near-infrared radiation intensity is in good agreement with the experimental results.The root mean square deviation(RMSD),mean bias deviation(MBD)and coefficient of determination(R~2)of the 0.870μm band are 6.906%,6.638%and 0.979,respectively.The RMSD,MBD and R~2 at 0.936μm band are 6.147%,6.120%and 0.946,respectively.The RMSD,MBD and R~2 of 1.020μm band are 6.214%,5.056%and 0.942,respectively.In addition,the results also show that the near-infrared 0.870～1.020μm band accounts for 9.200%of the total solar radiation intensity(blackbody radiation function).The results of this paper provide some reference for the calculation of near-infrared radiation intensity and the efficient use of solar energy.