Heliostat Wind Load Field Measurements at the University of Adelaide Atmospheric Boundary Layer Research Facility (ABLRF)

Abstract

The University of Adelaide has recently commissioned a facility dedicated to investigating the atmospheric boundary layer (ABL) for the analysis of wind loads on full-scale heliostats. Wind tunnel testing is an affordable way to analyse loads on a scaled structure before committing to a full-scale design. Scale testing however has its challenges as most cases in literature fail to correctly scale the ABL when scaling a model due to the differences between the ratio of the heliostat chord to the boundary layer depth in a wind tunnel and ABL. There is a lack of direct comparison between wind tunnel and full-scale heliostat wind loads. The Atmospheric Boundary Layer Research Facility (ABLRF) consists of arrays of ultrasonic anemometers and a 1.5 aspect ratio heliostat, mounted on a 6-axis load cell, for the comparison of loads measured in the wind tunnel with a full-scale model. Preliminary results categorise the site to have a roughness of 0.01 m to 0.03 m indicating open country farmland, when compared to standards. Comparison between coefficients of lift force, drag force, and hinge moment on the heliostat model at a single elevation angle at the ABLRF and wind tunnel models in literature verify the commissioning of the site, allowing for further in-depth analysis of wind load coefficients at varying elevation and azimuth angles.