日照作用下钢管混凝土构件截面温度场有限元分析

Finite Element Analysis on Temperature Field of CFST Members under Solar Radiation

提出日照作用下钢管混凝土构件截面温度场的有限元计算方法。日照作用下钢管混凝土构件表面的热流考虑钢管外表面与周围大气之间的对流换热、太阳辐射引起的钢管表面的辐射换热和钢管表面吸收的太阳辐射能,从而将边界条件简化为用牛顿传导定律表达的第3类边界条件。通过将构件表面分成4个区域来实现日照边界条件中太阳辐射强度的简化计算,其中,竖立构件表面可分为东、西、南、北朝向面上的太阳辐射;横放构件表面可分为东、西、水平面上的太阳辐射和仅与大气产生对流换热的一面。算例分析表明,有限元计算结果与实测结果吻合良好,可供今后研究和工程应用参考。今后有必要对通用程序进行二次开发,以简化目前复杂的太阳辐射作用的计算。

A finite element method to calculate the temperature field of Concrete Filled Steel Tubular （CFST） members under solar radiation was presented. The convection heat flux between the surface and the air, the heat flux caused by solar radiation and the heat flux absorbed from the sun were taken as the heat flux of CFST members under solar radiation. The solar radiation was simulated by the third boundary condition which was expressed by Newton＇ s convection law when considering the solar radiation. The CFST member surface was divided into four areas to realize the calculation of solar radiation, for the vertically placed member, the surface of member can be divided into face of east, west, south and north; and for the horizontally placed member, the surface of member can be divided into the face of east, west, horizontal surface, and the face where only heat convention happens. Case study shows that the calculating results agree well with the test results and can be a reference for further research and application for engineering. It is necessary to carry out secondary development of general program in the future to simplify the complicated solar radiation calculation.