Dyson V6 Operating Manual page 28

Air knives
A Dyson engineer discovered that a high speed
sheet of air can act as an invisible wiper blade,
literally scraping water from hands. With a
400mph airflow, the Dyson AirbladerM hand
dryer takes just twelve seconds and uses less
energy than warm air hand dryers. But it's only
possible because of the Dyson digital motor.