Does anyone know what the equations governing the effects of whistling in a convoluted tube as air passes trough it are? I didn't know it was called this until today, but a convoluted tube is the real name for what many cable management tubes are. These tubes are also used in medicine for things like ventilators. You used to be able purchase large ones as a toys, which you could twirl around above your head. The faster you twirl them, the higher pitch whistle you could get out of it. Thanks!