Effect of Non-Uniform Solar Temperature Field on Cable-Net Structure of Reflector of Large Radio Telescope-FAST

Abstract

The effect of a non-uniform solar temperature field on the cable-net structure of the reflector of a five-hundred-meter aperture spherical radio telescope-FAST was analyzed using the thermal analysis module of ANSYS. The integral parametric finite element model of the reflector structure with its measured landform was built, and the boundary conditions of periodic air temperature, solar radiation, long-wave radiation and shadows of surrounding environment, etc, were computed at intervals of half an hour under a cloudless sky on a summer day, as one of the worst-case climate conditions. The transient structural temperatures were then analyzed under sunshine which lasted for several days with a rational initial structural temperature distribution until the whole set of structural temperatures converged to the results obtained the day before. The corresponding structural analysis was then carried out. The results indicate that the highest local temperature difference goes up to 11° and the maximum r.m.s. error of fitting of the reflector geometry is about 2.2mm.