A ducted fan is a propulsion arrangement whereby a fan, which is a type of propeller, is mounted within a cylindrical shroud or duct. The duct reduces losses in thrust from the tip vortices of the fan, and varying the cross-section of the duct allows the designer to advantageously affect the velocity and pressure of the airflow according to Bernoulli's Principle. Ducted fan propulsion is used in aircraft, airships, airboats, hovercraft and fan packs.
Ducted fans normally have more and shorter blades than propellers and thus can operate at higher rotational speeds.
Read more about Ducted Fan: Applications, Advantages, Disadvantages
Famous quotes containing the word fan:
“Hard times accounted in large part for the fact that the exposition was a financial disappointment in its first year, but Sally Rand and her fan dancers accomplished what applied science had failed to do, and the exposition closed in 1934 with a net profit, which was donated to participating cultural institutions, excluding Sally Rand.”
—For the State of Illinois, U.S. public relief program (1935-1943)