A Method for the Calculation of the Design Wind Loads on Heliostats

This experimental study outlines a method to calculate the design wind loads on heliostats, based on peak wind load coefficients reported in the heliostat literature and aerodynamic shape factors derived from high-frequency pressure measurements on an isolated heliostat at different elevation and azimuth angles in a boundary layer wind tunnel. The results show that the aerodynamic shape factors are largest for a range of heliostat configurations, including elevation angles of 15 degrees, 30 degrees and 45 degrees and azimuth angles of 0 degrees and 45 degrees. The distribution of shape factors indicates that the leading edge of the heliostat is most vulnerable to wind-induced mirror damage in this range of critical elevation angles for heliostat design wind loads. The method proposed in the current study for heliostats conforms to the procedure used in design wind codes and standards for buildings and roof-mounted solar panels.