Click for PDF, with all graphs included by Richard James, Noise Engineer (7/8/14)
As the blade passes the tower, the low frequency noise and infrasound is generated at a frequency related to the hub’s rotation and number of blades. These pressure pulsations appear as tones during analysis, but are not heard as tones by most people. Instead, they may feel the pressure changes as pulsations, internal organ vibrations, or as a pain (like ear aches or migraines)
European Platform Against Windfarms