downwash


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downwash

[′dau̇n‚wäsh]
(fluid mechanics)
The downward deflection of air, relative to the direction of motion of an airfoil.

downwash

downwash
downwashclick for a larger image
downwash
downwash
i. Fluid flow moving at a deflected angle after deflection by helicopter rotors and measured parallel to the disc.
ii. Fluid flow deflected at an angle more perpendicular to the motion of the airfoil, measured in the plane parallel to the plane of symmetry close behind the trailing edge.
iii. Air that has passed around the main wing or rotor and now strikes the tailplane at an angle different from the direction of flight.
iv. Air that has been accelerated downward by the action of the rotors of a helicopter.
References in periodicals archive ?
When considering the base pressure distributions, on the single instance discussed, the indication is that the wake switched from an up-wash dominated wake to a downwash dominated wake with the introduction of the 15[degrees] taper, showing it to be a non-trivial modification.
(iv) Vortex generation and different types of mechanism such as separation of flow, upwash, and downwash are happened due to dynamic behavior of wind flow.
"Safety is paramount while underneath the bird, because you have so many variables with the downwash of the aircraft," said Cpl.
In this previous study, effects of circulation, thickness, and compressibility were retained, while the effects of shed vorticity and downwash were not modeled.
AIM 7-3-7, "WakeTurbulence," lays down some good words of warning: "In a slow hover taxi or stationary hover near the surface, helicopter main rotor(s) generate downwash producing high velocity outwash vortices to a distance approximately three times the diameter of the rotor ...
An analytical expression was developed which showed that wing/tail interference drag was determined by wing downwash at downstream infinity [11,12].
As an alternative, researchers at Washington State University, in collaboration with Digital Harvest, Inc., and Yamaha Precision Agriculture, are evaluating a 88 kg (194 lb) mid-size helicopter-type UAS with 3.1 m (10 ft) diameter rotor to determine if the downwash from the rotor is suitable for effective removal of rainwater in modern cherry canopies.
Three soldiers lost legs in explosions and Mark was fatally wounded when the downwash from the rotors of a Chinook helicopter trying to rescue them set off another of the mines.
"The larger size and weight of the Sikorsky S92 aircraft creates a slightly stronger downwash than the Sea King.
Shockingly, the boat did exactly what the HRST master and Seawolf Manual said it would: it got blown away by the rotor downwash. I steadily worked toward the boat, and it steadily worked away.
The downwash of the rotors rippled across the surface of the water.