Single-axis solar trackers have been widely used in photovoltaic (PV) systems due to their cost-effectiveness. However, aerodynamic instability of this structure, i.e., torsional flutter, frequently occurs when wind speed exceeds the critical threshold, leading to significant damage to the tracker. In this study, wind tunnel tests on a sectional model are conducted to better understand the mechanism of such torsional flutter. The effects of tilt angle, torsional frequency, damping ratio, and turbulence intensity are discussed in detail. Results show that the tilt angle significantly influences the critical wind speed and fluid–structure interaction. Stronger fluid–structure coupling effects occur at smaller tilt angles. The critical wind speeds at 0° and large tilt angles (e.g., greater than 40°) are much higher than those in the range of 10°–35°. The increase in structural torsional frequency can considerably increase the critical wind speed, whereas the effect of structural damping ratio and turbulence intensity on aerodynamic stability is relatively limited. Based on these findings, this study also provides recommendations for the wind-resistance design of PV tracker structures.
Wang et al. (Wed,) studied this question.