Pure tone generation and high directivity-index of a 36 HZ resonance in a fly-over by a wind-speed of 10 M/S

摘要

The wind under a fly-over generates in the Helmholz resonators tones from 35-37 Hz. At great distance from the fly-over a frequency of 36 Hz is found from a place 60 meters behind the fly-over. This type of source is hardly recognizable in the field because the place of the source is not at the place of the construction.