Determination of wind loads on heliostats

Abstract

By boundary layer wind tunnel measurements the wind loads on heliostats were investigated for conditions with no or only insufficient values available in literature:
\n•\tAspect ratio: For aspect ratios of the mirror plane (width / height) between 0.5 and 3.0 the wind load coefficients were determined. For the critical load cases (combinations of elevation angle and wind direction of highest wind loads) formulas for the calculation of the impact of the aspect ratio were gained.
\n•\tWide gap: By measurements of a heliostat with one wide central gap between the mirror facets it turned out that wide gaps are of impact especially on the hinge moment.
\n•\tWind fence: The impact of a wind fence at different heliostat field densities was investigated. For low field densities only small load reductions were measured.
\nFuture work should investigate the significance of the similarity of the energy spectrum at the critical scales.