Study On Heterogeneous Temperature Effect Of Large Span Structures Under Solar Radiation

Nowadays,the span of spatial structures is broken continually.More large–spanstructures appear,which include large outdoor components or large area transparentroof.The influence of solar radiation on large-span structure cannot beignored.However,the value of the solar radiation absorption coefficient,which isimportant to the research, is not standardized.At the same time,the analysis of thestructure temperature field is not accurate without considering the influence of fluidair.In this paper, spectrophotometer is used to test the solar radiation absorptioncoefficient of common steel coatings and aluminum.The influence of primer,intermediate coating,top coating on the solar radiation absorption coefficient isstudied.The solar radiation absorption coefficient of different colors includingwhite,grey,red,yellow,green and different top coatings including fluorocarbon,polyurethane, chlorinated rubber, and fire retardant coatings,aluminum is given.Temperature measurement experiment by thermocouple is carried out to validatethe accuracy of the test method of the solar radiation absorption coefficient.Theresults show that the temperature measurement experiment is viable.The test methodof the solar radiation absorption coefficient is right and the variation of the solarradiation absorption coefficient is consistent with temperature.Finite element analysis software Fluent is applied to study the non-uniform andtime variation thermal effect of large-span spatial structure under the solarradiation,which fluid air is also considered.The results show that the temperaturefield is more accurate after considering the influence of air,and the temperature fieldis not consistent with the heat flux field any more.The contour of temperature field isnot regular circle.The temperature is lower up to3.1℃with the consideration of air,and thetemperature ranges from25.0℃to58.1℃.The highest temperature is higher than thesurrounding temperature up to18.1℃.Compared with the results without consideringnon-uniform thermal effect,the maximum displacement of structure increases51.7%and the maximum von-Mises stress increases23.3%.It’s necessary to analyze the non-uniform thermal effect of large-span structure under solar radiation withconsideration of fluid air.