If you’re interested in the music of Whirly Tubes, and the physics behind it, the late Dr. Paul Doherty’s website may be just the thing for you. There you will find (amongst many other things) sections on :
What Notes Do Whirlies Sing?
What makes a whirly sing?
Math Root the connection between the frequency of the note and the frequency of rotation.
The Speed of Airflow Inside the Whirly