- /wind/, Aeron.a tubular chamber or structure in which a steady current of air can be maintained at a controlled velocity, equipped with devices for measuring and recording forces and moments on scale models of complete aircraft or of their parts or, sometimes, on full-scale aircraft or their parts.[1910-15, Amer.]
* * *Device for producing a controlled stream of air to study the effects on objects such as aircraft moving through air or the effects of moving air on models of stationary objects such as buildings.Applications of wind-tunnel research range from testing of airframes (the structures of aircraft and spacecraft) to research on the boundary layer, turbulence, drag, and lift. Measurements of air pressure and other characteristics at many points on the model yield information about how the total wind load is distributed. In addition to testing the effects of wind on aircraft and spacecraft, studies in wind tunnels have been used to solve design problems in automobiles, boats, trains, bridges, and buildings. See also aerodynamics.
* * *▪ aeronautical engineeringdevice for producing a controlled stream of air in order to study the effects of movement through air or resistance to moving air on models of aircraft and other machines and objects. Provided that the airstream is properly controlled, it is immaterial whether the stationary model under testing is designed to move through the air, as an aircraft, or to withstand wind pressures while standing in place, as a building.In open-ended wind tunnels of the early 20th century, air traveled slowly through a large-bore section of the tunnel, was accelerated in the nozzlelike test section, and slowed again in the large-bore diffuser section before being released into the atmosphere. Because little control could be exercised over the pressure, temperature, and humidity of the air in such an open-circuit tunnel, it was supplanted by a closed-circuit design in which air blown through the test section was contained in the circular or rectangular tunnel, passed through fans, and cycled back to the test section with the aid of turning vanes. Air velocity is controlled by changing the speed of the rotating fans or by adjusting the angle of the fan blades. In high-velocity tunnels, water-cooling systems are installed in the low-speed sections to cool the recycled air.Wind tunnels are classified as low-speed or high-speed; they are further classified as subsonic (80 percent of the speed of sound), transonic (about the speed of sound), supersonic (up to 6 times the speed of sound), hypersonic (6 to 12 times the speed of sound), and hypervelocity (over 12 times the speed of sound). To duplicate temperatures of flight at speeds of 10,000 miles (16,000 km) per hour and more, the test air must be heated well above the melting point of ordinary structural materials; consequently, such tunnels are operated on an impulse principle and only for extremely short periods of time on the order of a few thousandths of a second.Applications of wind-tunnel research range from routine testing of airframes to fundamental research on the boundary layer, the slow-moving layer of air adjacent to any wind-exposed body surface. Measurements of air pressure and other characteristics at many points on the model yield information about how the total wind load is distributed. In addition to aircraft and spacecraft, aerodynamic studies in wind tunnels have been highly profitable devices for solving design problems in automobiles, boats, trains, bridges, and building structures.
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wind tunnel — ► NOUN ▪ a tunnel like apparatus for producing an airstream past models of aircraft, buildings, etc., in order to investigate flow or the effect of wind on the full size object … English terms dictionary
wind tunnel — ☆ wind tunnel n. a tunnel like chamber through which air is forced and in which airplanes, motor vehicles, etc., or their scale models, are tested to determine the effects of wind pressure … English World dictionary
Wind tunnel — A wind tunnel is a research tool developed to assist with studying the effects of air moving over or around solid objects.Ways that wind speed and flow are measured in wind tunnels: * Threads can be attached to the surface of study objects to… … Wikipedia
wind tunnel — noun a structure resembling a tunnel where air is blown at known velocities for testing parts of aircraft • Hypernyms: ↑structure, ↑construction * * * noun, pl ⋯ nels [count] : a long, narrow room through which air is blown in order to test the… … Useful english dictionary
wind tunnel — UK [ˈwɪnd ˌtʌn(ə)l] / US noun [countable] Word forms wind tunnel : singular wind tunnel plural wind tunnels 1) a long thin room where planes and other vehicles are tested by forcing currents of air past them 2) a narrow place surrounded by high… … English dictionary
wind tunnel — [[t]wɪ̱nd tʌn(ə)l[/t]] wind tunnels N COUNT A wind tunnel is a room or passage through which air can be made to flow at controlled speeds. Wind tunnels are used to test new equipment or machinery, especially cars and aeroplanes … English dictionary
wind tunnel — /ˈwɪnd tʌnəl/ (say wind tunuhl) noun a tunnel like device through which a controlled airstream can be drawn at various speeds, in order to subject scale models of aircraft, vehicles, buildings, etc., to aerodynamic tests … Australian English dictionary
wind tunnel — tunnel (or a tubular room or structure) where wind is created to test parts of aircrafts or a completer aircraft … English contemporary dictionary
wind tunnel — wind tun|nel [ wınd ,tʌnl ] noun count 1. ) a long thin room where airplanes and other vehicles are tested by forcing currents of air past them 2. ) a place surrounded by buildings where there is always a lot of wind … Usage of the words and phrases in modern English
wind tunnel — wind tun|nel [ˈwınd ˌtʌnl] n a large enclosed passage where engineers test aircraft etc by forcing air past them … Dictionary of contemporary English