The Coanda effect is the tendency of a stream of fluid to stay attached to a convex surface, rather than follow a straight line in its original direction. The principle was named after Romanian inventor Henri Coandă, who was the first to understand the practical importance of the phenomenon for aircraft development. He made the discovery during experiments with his Coanda-1910 aircraft, which is the first aircraft based on a jet engine. A subset of the phases of matter, fluids include liquids, gases, plasmas and, to some extent, plastic solids. ... Henri Marie Coandă (June 7, 1886 – November 25, 1972) was a Romanian inventor, aerodynamics pioneer and the parent of the modern jet aircraft. ... The Coanda-1910 was an aircraft built by Romanian inventor Henri Coanda and exhibited by him at the Second International Aeronautical Exhibition in Paris around October 1910. ... A Pratt and Whitney turbofan engine for the F-15 Eagle is tested at Robins Air Force Base, Georgia, USA. The tunnel behind the engine muffles noise and allows exhaust to escape. ...

It has important applications in various high-lift devices on aircraft, where air moving over the wing can be "bent down" towards the ground using flaps. It was first implemented in a practical sense during the U.S. Air Force's AMST project. Several aircraft, notably the Boeing YC-14, have been built to take advantage of this effect by mounting jet engines on the top of wing to provide high-speed air even at low flying speeds, but to date only one aircraft has gone into production using this system, the Antonov An-72 'Coaler'. The McDonnell Douglas YC-15 and its successor, the Boeing C-17 Globemaster III also employ the effect, though to a less substantial degree. An aircraft is any machine capable of atmospheric flight. ... Seal of the Air Force. ... Boeing YC-14 McDonnell-Douglas YC-15 The Advanced Medium STOL Transport (AMST) project was intended to replace the Lockheed C-130 Hercules tactical transport in USAF service. ... Categories: Stub | Defence companies | Boeing | U.S. aircraft manufacturers ... Boeing YC-14 The YC-14 was Boeings entry into the USAFs Advanced Medium STOL Transport (AMST) competition, to replace the C-130 Hercules as the USAFs standard STOL tactical transport. ... A Pratt and Whitney turbofan engine for the F-15 Eagle is tested at Robins Air Force Base, Georgia, USA. The tunnel behind the engine muffles noise and allows exhaust to escape. ... Private Antonov AN-2 in the UK Antonov, aka Antonov Aeronautical Scientific/Technical Complex (Antonov ASTC) (Ukrainian: ) is a Ukraine-based (since 1952) aircraft manufacturing and services company (design office prefix An) with particular expertise in the field of very large aircraft construction. ... An-72 aircraft Designed as a strategic military freighter, the Antonov An-72 (NATO reporting name Coaler) was intended as a replacement for the An-26, but variants have found success as commercial freighters. ... McDonnell-Douglas YC-15 The YC-15 was McDonnell-Douglas entry into the USAFs Advanced Medium STOL Transport (AMST) competition, to replace the C-130 Hercules as the USAFs standard STOL tactical transport. ... The C-17 Globemaster III The C-17 Globemaster III is a strategic airlifter manufactured by Boeing IDS, used by the United States Air Force and the Royal Air Force. ...

Closely following the work of Henri Coanda on applications of the Coanda effect, and in particular the work on Aerodina Lenticulara, John Frost of Avro Canada also spent considerable time researching the effect, leading to a series of "inside out" hovercraft-like aircraft where the air exited in a ring around the outside of the aircraft and was directed by being "attached" to a flap-like ring. This is as opposed to a traditional hovercraft design in which the air is blown into a central area, the plenum, and directed down with the use of a fabric "skirt". Only one of Frost's designs was ever built, the Avrocar. Henri Marie Coandă (June 7, 1886 - November 25, 1972) was a Romanian inventor, aerodynamics pioneer and the parent of the modern jet aircraft. ... Avro Aircraft Canada was a Canadian aircraft manufacturing company, known for their innovative designs, including the famed Avro Arrow fighter. ... A U.S. Navy hovercraft attached to the Amphibious assault ship Kearsarge (LHD-3) A hovercraft, or air-cushion vehicle, is a vehicle or craft that can be supported by a cushion of air ejected downwards against a surface close below it, and can in principle travel over any relatively... This article needs to be cleaned up to conform to a higher standard of quality. ...

Demonstration

If one holds the back of a spoon close to (but not touching) a stream of water running freely out of a tap (faucet), the stream of water will deflect from the vertical in order to run over the back of the spoon. This is the Coanda Effect in action.

This demonstration is the combination of the Venturi effect and the Coanda effect. The Venturi effect would cause a drop in pressure between the spoon and the stream of water which would then be drawn towards the spoon. Once the surface of the stream hits the spoon the Coanda effect keeps it running over the convex surface. The Venturi effect is a special case of the Bernoulli effect, in the case of fluid or air flow through a tube or pipe with a constriction in it. ...

See also

• Aerodynamics
• Fluid dynamics
• Boundary layer

Aerodynamics is a branch of fluid dynamics concerned with the study of gas flows, first analysed by George Cayley in the 1800s. ... This article or section should be merged with Fluid mechanics Fluid dynamics is the study of fluids (liquids and gases) in motion, and the effect of the fluid motion on fluid boundaries, such as solid containers or other fluids. ... In physics and fluid mechanics, the boundary layer is that layer of fluid in the immediate vicinity of a bounding surface. ...

External links

• Coanda Effect: Understanding Why Wings Work
• Coanda Effect example