Experimental study on wind-induced vibration and aerodynamic interference effects of flexible photovoltaics

This study investigates the wind-induced vibrations (WIVs) of photovoltaic (PV) modules possessing unique characteristics such as lightweight construction, low frequency, and susceptibility to wind loads, in contrast to stationary PV systems installed on rooftops and ground surfaces. The complex interference effects within rows of flexible PV arrays were investigated under varying angles of wind attack (AOAs) and inter-row distances, specifically focusing on wind directions of 0 degrees and 180 degrees. A comparative analysis of the WIV of a single row was also conducted. The findings indicated that both single- and multi-row PV modules experience flutter instability as wind speeds increase, resulting in significant vibrations at wind directions of 0 degrees and 180 degrees. Vertical vortex- induced vibrations (VIVs) were observed in multi-row arrays at lower wind speeds prior to the onset of flutter instability, whereas no VIVs occurred in the single-row configuration. Within the three-row array, the middle row exhibited the most significant VIVs. An increase in AOA was found to correlate with elevated maximum VIV responses, wind speed, and vortex amplitude. Throughout various flutter instability scenarios, the third row consistently maintained stable. Notably, the critical wind speed for flutter was lower at a wind direction of 180 degrees, and the VIV response was more pronounced compared to that observed at 0 degrees.