Wind tunnel 1

Wind tunnel

NASA wind tunnel with the model of a plane.

A model Cessna with helium-filled bubblesshowing streamlines of the wingtip vortices.

A wind tunnel is a research tool usedin aerodynamic research. It is used tostudy the effects of air moving pastsolid objects.

Theory of operation

Wind tunnels were first proposed as ameans of studying automobiles(primarily airplanes) in free flight. Thewind tunnel was envisioned as a meansof reversing the usual paradigm:instead of the air's standing still andthe aircraft moving at speed through it,the same effect would be obtained ifthe aircraft stood still and the airmoved at speed past it. In that way astationary observer could study theaircraft in action, and could measurethe aerodynamic forces being imposedon the aircraft.

Later, wind tunnel study came into itsown: the effects of wind on manmadestructures or objects needed to bestudied, when buildings became tallenough to present large surfaces to thewind, and the resulting forces had to beresisted by the building's internal structure. Determining such forces was required before building codes couldspecify the required strength of such buildings.

Still later, wind-tunnel testing was applied to automobiles, not so much to determine aerodynamic forces per se butmore to determine ways to reduce the power required to move the vehicle on roadways at a given speed. In thesestudies, the interaction between the road and the vehicle plays a significant role, and this interaction must be takeninto consideration when interpreting the test results. In an actual situation the roadway is moving relative to thevehicle but the air is stationary relative to the roadway, but in the wind tunnel the air is moving relative to theroadway, while the roadway is stationary relative to the test vehicle. Some automotive-test wind tunnels haveincorporated moving belts under the test vehicle in an effort to approximate the actual condition.

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Measurement of aerodynamic forcesWays that air velocity and pressures are measured in wind tunnels:• air velocity through the test section is determined by Bernoulli's principle. Measurement of the dynamic pressure,

the static pressure, and (for compressible flow only) the temperature rise in the airflow• direction of airflow around a model can be determined by tufts of yarn attached to the aerodynamic surfaces• direction of airflow approaching an aerodynamic surface can be visualized by mounting threads in the airflow

ahead of and aft of the test model• dye, smoke, or bubbles of liquid can be introduced into the airflow upstream of the test model, and their path

around the model can be photographed (see particle image velocimetry)• pressures on the test model are usually measured with beam balances, connected to the test model with beams or

strings or cables• pressure distributions across the test model have historically been measured by drilling many small holes along

the airflow path, and using multi-tube manometers to measure the pressure at each hole• pressure distributions can more conveniently be measured by the use of pressure-sensitive paint, in which higher

local pressure is indicated by lowered fluorescence of the paint at that point• pressure distributions can also be conveniently measured by the use of pressure-sensitive pressure belts, a recent

development in which multiple ultra-miniaturized pressure sensor modules are integrated into a flexible strip. Thestrip is attached to the aerodynamic surface with tape, and it sends signals depicting the pressure distributionalong its surface.[1]

• pressure distributions on a test model can also be determined by performing a wake survey, in which either asingle pitot tube is used to obtain multiple readings downstream of the test model, or a multiple-tube manometeris mounted downstream and all its readings are taken (often by photograph).

History

OriginsEnglish military engineer and mathematician Benjamin Robins (1707–1751) invented a whirling arm apparatus todetermine drag and did some of the first experiments in aviation theory.Sir George Cayley (1773–1857) also used a whirling arm to measure the drag and lift of various airfoils. Hiswhirling arm was 5 feet (1.5 m) long and attained top speeds between 10 and 20 feet per second.However, the whirling arm does not produce a reliable flow of air impacting the test shape at a normal incidence.Centrifugal forces and the fact that the object is moving in its own wake mean that detailed examination of theairflow is difficult. Francis Herbert Wenham (1824–1908), a Council Member of the Aeronautical Society of GreatBritain, addressed these issues by inventing, designing and operating the first enclosed wind tunnel in 1871. Oncethis breakthrough had been achieved, detailed technical data was rapidly extracted by the use of this tool. Wenhamand his colleague Browning are credited with many fundamental discoveries, including the measurement of l/dratios, and the revelation of the beneficial effects of a high aspect ratio.Carl Rickard Nyberg used a wind tunnel when designing his Flugan from 1897 and onwards.In a classic set of experiments, the Englishman Osborne Reynolds (1842–1912) of the University of Manchesterdemonstrated that the airflow pattern over a scale model would be the same for the full-scale vehicle if a certain flowparameter were the same in both cases. This factor, now known as the Reynolds Number, is a basic parameter in thedescription of all fluid-flow situations, including the shapes of flow patterns, the ease of heat transfer, and the onsetof turbulence. This comprises the central scientific justification for the use of models in wind tunnels to simulatereal-life phenomena. However, there are limitations on conditions in which dynamic similarity is based upon theReynolds number alone.

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Replica of the Wright brothers' wind tunnel.

German aviation laboratory, 1935

The Wright brothers' use of a simple wind tunnel in1901 to study the effects of airflow over various shapeswhile developing their Wright Flyer was in some waysrevolutionary.[2] It can be seen from the above,however, that they were simply using the acceptedtechnology of the day, though this was not yet acommon technology in America.

Subsequent use of wind tunnels proliferated as thescience of aerodynamics and discipline of aeronauticalengineering were established and air travel and powerwere developed.The US Navy in 1916 built one of the largest windtunnels in the world at that time at the WashingtonNavy Yard. The inlet was almost 11 feet (3.4 m) indiameter and the discharge part was 7 feet (2.1 m) indiameter. A 500 hp electric motor drove the paddletype fan blades.[3]

Wind tunnels were often limited in the volume andspeed of airflow which could be delivered.

World War Two

In 1941 the US constructed one of the largest windtunnels at that time at Wright Field in Dayton, Ohio.This wind tunnel starts at 45 feet (14 m) and narrows to20 feet (6.1 m) in diameter. Two 40-foot (12 m) fanswere driven by a 40,000hp electric motor. Large scaleaircraft models could be tested at air speeds of 400 mph(644 km/h).[4]

The wind tunnel used by German scientists atPeenemünde prior to and during WWII is an interestingexample of the difficulties associated with extendingthe useful range of large wind tunnels. It used somelarge natural caves which were increased in size byexcavation and then sealed to store large volumes of airwhich could then be routed through the wind tunnels.This innovative approach allowed lab research inhigh-speed regimes and greatly accelerated the rate of advance of Germany's aeronautical engineering efforts. By theend of the war, Germany had at least three different supersonic wind tunnels, with one capable of Mach 4.4 (heated)airflows.[5]

Wind tunnel 4

Post World War TwoLater research into airflows near or above the speed of sound used a related approach. Metal pressure chambers wereused to store high-pressure air which was then accelerated through a nozzle designed to provide supersonic flow.The observation or instrumentation chamber ("test section") was then placed at the proper location in the throat ornozzle for the desired airspeed.For limited applications, Computational fluid dynamics (CFD) can augment or possibly replace the use of windtunnels. For example, the experimental rocket plane SpaceShipOne was designed without any use of wind tunnels.However, on one test, flight threads were attached to the surface of the wings, performing a wind tunnel type of testduring an actual flight in order to refine the computational model. It should be noted that, for situations whereexternal turbulent flow is present, CFD is not practical due to limitations in present day computing resources. Forexample, an area that is still much too complex for the use of CFD is determining the effects of flow on and aroundstructures, bridges, terrain, etc.

Preparing a model in the Kirsten Wind Tunnel, asubsonic wind tunnel at the University of

Washington

The most effective way to simulative external turbulent flow is throughthe use of a boundary layer wind tunnel.There are many applications for boundary layer wind tunnel modeling.For example, understanding the impact of wind on high-rise buildings,factories, bridges, etc. can help building designers construct a structurethat stands up to wind effects in the most efficient manner possible.Another significant application for boundary layer wind tunnelmodeling is for understanding exhaust gas dispersion patterns forhospitals, laboratories, and other emitting sources. Other examples ofboundary layer wind tunnel applications are assessments of pedestriancomfort and snow drifting. Wind tunnel modeling is accepted as amethod for aiding in Green building design. For instance, the use ofboundary layer wind tunnel modeling can be used as a credit forLeadership in Energy and Environmental Design (LEED) certificationthrough the U.S. Green Building Council.

Fan blades of Langley Research Center's 16 foot transonic windtunnel in 1990, before it was mothballed in 2004.

Wind tunnel tests in a boundary layer wind tunnelallow for the natural drag of the Earth's surface to besimulated. For accuracy, it is important to simulate themean wind speed profile and turbulence effects withinthe atmospheric boundary layer. Most codes andstandards recognize that wind tunnel testing canproduce reliable information for designers, especiallywhen their projects are in complex terrain or onexposed sites.In the USA many wind tunnels have beendecommissioned in the last 20 years, including somehistoric facilities. Pressure is brought to bear onremaining wind tunnels due to declining or erratic

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usage, high electricity costs, and in some cases the high value of the real estate upon which the facility sits. On theother hand CFD validation still requires wind-tunnel data, and this is likely to be the case for the foreseeable future.Studies have been conducted and others are under way to assess future military and commercial wind tunnel needs,but the outcome remains uncertain.[6] More recently an increasing use of jet-powered, instrumented unmannedvehicles ["research drones"] have replaced some of the traditional uses of wind tunnels.[7]

How it works

Six-element external balance below the KirstenWind Tunnel

Air is blown or sucked through a duct equipped with a viewing portand instrumentation where models or geometrical shapes are mountedfor study. Typically the air is moved through the tunnel using a seriesof fans. For very large wind tunnels several meters in diameter, asingle large fan is not practical, and so instead an array of multiple fansare used in parallel to provide sufficient airflow. Due to the sheervolume and speed of air movement required, the fans may be poweredby stationary turbofan engines rather than electric motors.

The airflow created by the fans that is entering the tunnel is itselfhighly turbulent due to the fan blade motion (when the fan is blowingair into the test section – when it is sucking air out of the test sectiondownstream, the fan-blade turbulence is not a factor), and so is notdirectly useful for accurate measurements. The air moving through thetunnel needs to be relatively turbulence-free and laminar. To correctthis problem, closely-spaced vertical and horizontal air vanes are usedto smooth out the turbulent airflow before reaching the subject of thetesting.

Due to the effects of viscosity, the cross-section of a wind tunnel is typically circular rather than square, becausethere will be greater flow constriction in the corners of a square tunnel that can make the flow turbulent. A circulartunnel provides a smoother flow.

The inside facing of the tunnel is typically as smooth as possible, to reduce surface drag and turbulence that couldimpact the accuracy of the testing. Even smooth walls induce some drag into the airflow, and so the object beingtested is usually kept near the center of the tunnel, with an empty buffer zone between the object and the tunnelwalls. There are correction factors to relate wind tunnel test results to open-air results.Lighting is usually recessed into the circular walls of the tunnel and shines in through windows. If the light weremounted on the inside surface of the tunnel in a conventional manner, the light bulb would generate turbulence as theair blows around it. Similarly, observation is usually done through transparent portholes into the tunnel. Rather thansimply being flat discs, these lighting and observation windows may be curved to match the cross-section of thetunnel and further reduce turbulence around the window.Various techniques are used to study the actual airflow around the geometry and compare it with theoretical results,which must also take into account the Reynolds number and Mach number for the regime of operation.

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Pressure measurementsPressure across the surfaces of the model can be measured if the model includes pressure taps. This can be useful forpressure-dominated phenomena, but this only accounts for normal forces on the body.

Force and moment measurements

A typical lift coefficient versus angle of attackcurve.

With the model mounted on a force balance, one can measure lift, drag,lateral forces, yaw, roll, and pitching moments over a range of angle ofattack. This allows one to produce common curves such as liftcoefficient versus angle of attack (shown).

Note that the force balance itself creates drag and potential turbulencethat will affect the model and introduce errors into the measurements.The supporting structures are therefore typically smoothly shaped tominimize turbulence.

Flow visualization

Because air is transparent it is difficult to directly observe the airmovement itself. Instead, multiple methods of both quantitative and qualitative flow visualization methods have beendeveloped for testing in a wind tunnel.

Qualitative methods• Smoke• TuftsTufts are applied to a model and remain attached during testing. Tufts can be used to gauge air flow patterns andflow separation.

Compilation of images taken during an alpha run starting at 0 degrees alpha ranging to 26degrees alpha. Images taken at the Kirsten Wind Tunnel using fluorescent mini-tufts.

Notice how separation starts at the outboard wing and progresses inward. Notice also howthere is delayed separation aft of the nacelle.

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Fluorescent mini-tufts attached to a wing in the Kirsten Wind Tunnel showing air flow directionand separation. Angle of attack ~ 12 degrees, speed ~120 Mph.

• Evaporating suspensionsEvaporating suspensions are simply a mixture of some sort or fine powder, talc, or clay mixed into a liquid with alow latent heat of evaporation. When the wind is turned on the liquid quickly evaporates leaving behind the clay in apattern characteristic of the air flow.

China clay on a wing in the Kirsten Wind Tunnel showing reverse and span-wise flow.

• OilWhen oil is applied to the model surface it can clearly show the transition from laminar to turbulent flow as well asflow separation.

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Oil flow vis on straight wing in the Kirsten WindTunnel. Trip dots can be seen near the leading

edge.

• FogFog (usually from water particles) is created with an ultrasonic piezoelectric nebulizer. The fog is transported insidethe wind tunnel (preferably of the closed circuit & closed test section type). An electrically heated grid is insertedbefore the test section which evaporates the water particles at its vicinity thus forming fog sheets. The fog sheetsfunction as streamlines over the test model when illuminated by a light sheet.

Fog (water particle) wind tunnel visualization ofa NACA 4412 airfoil at a low speed flow

(Re=20.000).

Video of a wind tunnel fog visualization [8]

• SublimationIf the air movement in the tunnel is sufficiently non-turbulent, aparticle stream released into the airflow will not break up as the airmoves along, but stay together as a sharp thin line. Multiple particlestreams released from a grid of many nozzles can provide a dynamicthree-dimensional shape of the airflow around a body. As with theforce balance, these injection pipes and nozzles need to be shaped in amanner that minimizes the introduction of turbulent airflow into theairstream.

High-speed turbulence and vortices can be difficult to see directly, but strobe lights and film cameras or high-speeddigital cameras can help to capture events that are a blur to the naked eye.High-speed cameras are also required when the subject of the test is itself moving at high speed, such as an airplanepropeller. The camera can capture stop-motion images of how the blade cuts through the particulate streams and howvortices are generated along the trailing edges of the moving blade.

ClassificationThere are many different kinds of wind tunnels, an overview is given in the list below:• Low speed wind tunnel• High speed wind tunnel• Supersonic wind tunnel• Hypersonic wind tunnel• Subsonic and transonic wind tunnel

Wind tunnel 9

List of wind tunnels• Modine Wind Tunnels, Climatic Wind Tunnel Testing, Large Truck and Automotive• AeroDyn Wind Tunnel, Full Scale NASCAR Racecars• A2 Wind Tunnel, Full scale general purpose• Eight-Foot High Speed Tunnel• Full Scale 30- by 60-Foot Tunnel• Trisonic Wind Tunnel• Unitary Plan Wind Tunnel• Wind Shear's Full Scale, Rolling Road, Automotive Wind Tunnel• Variable Density Tunnel

Vertical wind tunnel T-105 at TsAGI used foraircraft testing (built in 1941)

Aquadynamic Flume

The aerodynamic principles of the wind tunnel work equally onwatercraft, except the water is more viscous and so imposes a greaterforces on the object being tested. A looping flume is typically used forunderwater aquadynamic testing. The interaction between 2 differenttypes of fluids means that pure windtunnel testing is only partlyrelevant. However, a similar sort of research is done in a towing tank

Low-speed Oversize Liquid Testing

Air is not always the best test medium to study small-scaleaerodynamic principles, due to the speed of the air flow and airfoilmovement. A study of fruit fly wings designed to understand how thewings produce lift was performed using a large tank of mineral oil andwings 100 times larger than actual size, in order to slow down the wingbeats and make the vortices generated by the insect wings easier to seeand understand.[9]

Fan testing

Wind tunnel tests are also performed to measuring the air movement of the fans at a specific pressure exactly. Bydetermining the environmental circumstances during the measuring and by revising the air-tightness afterwards, thestandardization of the data is warranted. There are 2 possible ways of measurement: a complete fan or an impeller ona hydraulic installation. Two measuring tubes enable measurements of lower air currents (< 30.000 m³/h) as well ashigher air currents (< 60.000 m³/h). The determination of the Q/h curve of the fan is one of the main objectives. Todetermine this curve (and to define other parameters) air technical, mechanical as well as electro technical data aremeasured:

Air technical:• Static pressure difference (Pa)• Amount of moved air (m³/h)• Average air speed (m/s)• Specific efficiency (W/1000m³/h)• EfficiencyElectro technical:• Tension (V)

Wind tunnel 10

• Current (A)• Cos φ• Admitted power (W) fan / impeller• Rotations per minute (RPM)The measurement can take place on the fan or in the application in which the fan is used.

Wind engineering testingIn Wind Engineering, Wind Tunnel Tests are often used to measure the velocity around, and forces or pressuresupon structures. Usually very tall buildings, buildings with unusual or complicated shapes (such as a tall buildingwith a parabolic or a hyperbolic shape), cable suspension bridges or cable stayed bridges are analysed in specializedatmospheric boundary layer wind tunnels. These feature a long upwind section to accurately represent the windspeed and turbulence profile acting on the structure. Wind tunnel tests provide the necessary design pressuremeasurements for use in the dynamic analysis of the structure.

References[1] Going with the flow, Aerospace Engineering & Manufacturing, March 2009, pp. 27-28 Society of Automotive Engineers[2] Dodson, MG (2005). "An Historical and Applied Aerodynamic Study of the Wright Brothers' Wind Tunnel Test Program and Application to

Successful Manned Flight" (http:/ / archive. rubicon-foundation. org/ 3585). US Naval Academy Technical Report USNA-334. . Retrieved2009-03-11.

[3] "US Navy Experimental Wind Tunnel" (http:/ / books. google. com/ books?id=V3fmAAAAMAAJ& pg=PA426& dq=Aero+ Club+ Of+America+ Flying& hl=en& ei=XbQqTeyqCdv4nwex5pHXAQ& sa=X& oi=book_result& ct=result& resnum=6&ved=0CEQQ6AEwBQ#v=onepage& q=Aero Club Of America Flying& f=true) Aerial Age Weekly, 17th January 1916, pages 426-427

[4] "400mph Wind Tests Planes" (http:/ / books. google. com/ books?id=mtkDAAAAMBAJ& pg=PA14& dq=popular+ mechanics+ July+1932+ airplane& hl=en& ei=1EAYTerQFOe6nAfUv-TTDg& sa=X& oi=book_result& ct=result& resnum=6&ved=0CDgQ6AEwBTgy#v=onepage& q=popular mechanics July 1932 airplane& f=true) Popular Mechanics, July 1941

[5] http:/ / www. space. co. uk/ DataBank/ VideoGallery/ VideoPlayer/ tabid/ 384/ VideoId/ 33/ Test-Pilot-Discussion. aspx[6] Goldstein, E., "Wind Tunnels, Don't Count Them Out," Aerospace America, Vol. 48 #4, April 2010, pp. 38-43[7] Benjamin Gal-Or, "Vectored Propulsion, Supermaneuverability & Robot Aircraft", Springer Verlag, 1990, ISBN 0-387-97161-0,

3-540-97161-0[8] http:/ / vimeo. com/ 24212774[9] Popular Science, Dec 2002 (http:/ / www. carlzimmer. com/ articles/ 2002/ articles_2002_Flyorama. html)

External links• Wind Tunnel Testing for Axial fans (http:/ / ventilation. vostermans. com/ en-v/ multifan/ support/ windtunnel)• Modine Vehicle Wind Tunnels (Racine, Wisconsin, USA) (http:/ / www. modine. com/ v2portal/ page/ portal/

modine/ modineDesignCenterDefault/ modine_com/ technology/ level_3_content_046. htm)• Construction of Wind Tunnels (Germany) (http:/ / www. tadka. de)• Wind Tunnel for Study of Insect Attractants and Sex Pheromones (http:/ / www. olfacts. nl/ index_bestanden/

Page4. html)• Wind Tunnel for Study of Beetle Responses to Plant Odours (http:/ / www. olfacts. nl/ index_bestanden/ Page6.

html)• Wichita State University 7 x 10 foot Beech Memorial Wind Tunnel (http:/ / www. niar. wichita. edu/ researchlabs/

ad_overview. asp)• Wind Tunnels of FORCE Technology: Climatic-, Boundary Layer- and Closed circuit Wind Tunnels (Lyngby,

Denmark) (http:/ / www. forcewindengineering. dk)• Windshear, Inc., Full-Scale 180 MPH Rolling-Road Wind Tunnel (Concord, North Carolina, USA) (http:/ / www.

windshearinc. com)• Danish Freefall Simulator Project – DFSP (http:/ / www. dfsp. dk) (First indoor vertical wind tunnel in Northern

Europe)

Wind tunnel 11

• Wind Tunnel Laboratory of Chang'an university (XI'AN CHINA) (http:/ / chdwt. chd. edu. cn)• Wind Tunnels of NASA (NASA SP-440, 1981) (http:/ / www. hq. nasa. gov/ office/ pao/ History/ SP-440/ cover.

htm)• German-Dutch Wind Tunnels (Germany and the Netherlands) (http:/ / www. dnw. aero/ )• Wind Tunnels of IAT-CNAM (FRANCE) (http:/ / www. cnam. fr/ instituts/ IAT/ index_en. htm)• Wind Tunnels of ONERA (FRANCE) (http:/ / windtunnel. onera. fr/ )• 4+ Boundary Layer Wind Tunnels (http:/ / www. rwdi. com/ resource/ wind_tunnels) at RWDI• Formula 1 wind tunnel at Toyota Motorsport GmbH, including photos and video (http:/ / www.

toyota-motorsport. com/ services/ wind-tunnel-support-services/ wind-tunnels. html)• Wind Engineering and Fluids Laboratory, Colorado State University (Fort Collins, Colorado) (http:/ / www.

windlab. colostate. edu/ index. htm)• 4 Boundary Layer Wind Tunnels (http:/ / www. cppwind. com/ about/ facilities/ facilities. html) at CPP• Boundary Layer Wind Tunnel, Univ. of Western Ontario (Canada) (http:/ / www. blwtl. uwo. ca/ Public/

Facilities. aspx)• VIPAC Engineers & Scientists (http:/ / www. vipac. com. au)• Wind tunnel of Helicopter Pionier Henrich Focke (GERMANY, Bremen 1890- +1979) (http:/ / www.

focke-windkanal. de)• Pininfarina Full Scale Automotive Wind Tunnel (http:/ / www. pininfarina. it/ arc)• University of Washington 8 x 12 foot Wind Tunnel (http:/ / www. uwal. org/ )• Aeronautical Testing Service, Inc. Wind Tunnel Model Manufacturer (http:/ / www. aerotestsvc. com/ )• Vertical Wind tunnel for Skydivers (Bedford, ENGLAND) (http:/ / www. bodyflight. co. uk)• Texas A&M University Low Speed Wind Tunnel (http:/ / wind. tamu. edu)• Embry-Riddle Aeronautical University Subsonic & Supersonic Wind Tunnel Laboratory (http:/ / www. erau. edu/

prescott/ engineering/ facilities_wind_tunnel. html)• Old Dominion University's Langley Full-Scale Tunnel (30x60) (http:/ / www. lfst. com/ )• Forschungsinstitut für Kraftfahrwesen und Fahrzeugmotoren Stuttgart, Research Institute of Automotive

Engineering and Vehicle Engines Stuttgart (http:/ / www. fkfs. de/ )• Climatic wind tunnel – Rail Tec Arsenal (rta – Vienna, AUSTRIA) (http:/ / www. rta. co. at/ )• Theodore von Kármán Wind Tunnel Laboratory, Budapest University of Technology and Economics (BME),

Hungary (http:/ / www. karman-wtl. com/ )• Remote operation of a wind tunnel via Internet to determine air friction of toy cars, Germany (English version

available) (http:/ / rcl. physik. uni-kl. de/ )• AEROLAB, LLC (http:/ / www. aerolab. com) (Wind Tunnel Design and Manufacturing)• ENGINEERING LABORATORY DESIGN,INC. (http:/ / www. eldinc. com) (Wind Tunnel & Water Tunnel

Design and Manufacturing)• Test SLATE – Automated Test Software for Wind Tunnels and Similar Test Facilities – by JACOBS (http:/ /

testslate. jacobstechnology. com/ )• WTtech.CZ (http:/ / www. wttech. cz) (Wind Tunnel Design and Manufacturing, Aerodynamics balances Design

and Manufacturing )• GAIUS (http:/ / www. imtech. nl/ SiteContent/ EUPortal/ Documenten/ Netherlands/ ICT/ TS/

Imtech_ICT_TS_GAIUS_en. pdf) Generic Automated Integrated Universal System: cross platform open sourceautomation system for industrial wind tunnels.

Article Sources and Contributors 12

Article Sources and ContributorsWind tunnel  Source: http://en.wikipedia.org/w/index.php?oldid=431346635  Contributors: A2Kafir, A3RO, Alansohn, Alexknight12, Ancheta Wis, BatteryIncluded, BenFrantzDale, BilCat,BobDrzyzgula, BokicaK, Brutaldeluxe, Bubba hotep, CambridgeBayWeather, Canterbury Tail, Canthusus, Charles Matthews, Chlewey, Cobberv, Commander Keane, CommonsDelinker,ComputerGeezer, Cosmic Latte, Cyfal, D, DARTH SIDIOUS 2, DMahalko, David.Monniaux, Dawnsmessage, De bezige bij, Denmueller, Dirrival, DonFB, Doncram, Dtom, Dzordzm, EMBaero,Econterms, EdH, Elipongo, Enisbayramoglu, Epbr123, Feťour, Flip, Fmm81can, Fongs, Frankenpuppy, Gene Hobbs, Georgepehli, Good Olfactory, Goodlysheep, Gphoto, GrahamN, Greencaterpillar, GregorB, Gunter, Hda3ku, Howcheng, IJA, IVAN3MAN, Iridescent, J.delanoy, JRHorse, Jackehammond, Japanese Searobin, Jbk12385, Jcmaco, JeLuF, Jeff220, Jmabel, Jmundo,Koavf, Kpuck1, KudzuVine, Leszek Jańczuk, Liftarn, Lockan, Logawi, Mac, Mac Davis, Manop, Marek69, Markos Strofyllas, Mattbondy, Mbubel, Mdrejhon, MementoVivere, Mirwin,Mr.Z-man, Mysid, Mythealias, Nbonneel, Oldmanbiker, Ortolan88, PZierhut, Pearle, Pengo, Peruvianllama, Philip Trueman, PierreAbbat, Pinethicket, Plenumchamber, Pooh, Praveen pillay,Prolog, Qutezuce, RaseaC, Raymondwinn, Rich Farmbrough, RivGuySC, Saperaud, Sdcoonce, SeanMack, Settles1, Shanes, Sladen, Stan J Klimas, Stephenb, Suruena, Swdwolf, Taichi, Tenisotl,Thadius856, The ed17, Thomas Larsen, Toytoy, Twang, UltimatesocCer, UncivilFire, Uwoljw, VectorVictor, Ventilationfans, Verbal, Vivaldi, Vojtamraz, Voyagerfan5761, Wolfc01,Wolfkeeper, Yuriybrisk, Zanhsieh, ZooFari, Zzuuzz, 244 anonymous edits

Image Sources, Licenses and ContributorsFile:Windkanal.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Windkanal.jpg  License: GNU Free Documentation License  Contributors: JeLuFFile:Cessna 182 model-wingtip-vortex.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Cessna_182_model-wingtip-vortex.jpg  License: Creative Commons Attribution-ShareAlike3.0 Unported  Contributors: BenFrantzDaleFile:WB Wind Tunnel.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:WB_Wind_Tunnel.jpg  License: Creative Commons Attribution-Sharealike 2.5  Contributors: Originaluploader was Axda0002 at en.wikipediaFile:Bundesarchiv Bild 102-17158, Deutsche Versuchsanstalt für Luftfahrt.jpg  Source:http://en.wikipedia.org/w/index.php?title=File:Bundesarchiv_Bild_102-17158,_Deutsche_Versuchsanstalt_für_Luftfahrt.jpg  License: Creative Commons Attribution-Share Alike 3.0 Germany Contributors: Martin H., MattesImage:Kirsten wind tunnel 05.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Kirsten_wind_tunnel_05.jpg  License: Creative Commons Attribution-ShareAlike 3.0 Unported Contributors: Joe MabelImage:Man examining fan of Langley Research Center 16 foot transonic wind tunnel.jpg  Source:http://en.wikipedia.org/w/index.php?title=File:Man_examining_fan_of_Langley_Research_Center_16_foot_transonic_wind_tunnel.jpg  License: Public Domain  Contributors: NASAImage:Kirsten wind tunnel 08A.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Kirsten_wind_tunnel_08A.jpg  License: Creative Commons Attribution-ShareAlike 3.0 Unported Contributors: Joe MabelImage:Lift curve.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Lift_curve.svg  License: Public Domain  Contributors: botag.File:GIF Flow visualization.gif  Source: http://en.wikipedia.org/w/index.php?title=File:GIF_Flow_visualization.gif  License: Creative Commons Attribution-Sharealike 3.0  Contributors:UWAL CrewFile:Minitufts on wing.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Minitufts_on_wing.jpg  License: Creative Commons Attribution-Sharealike 3.0  Contributors: UWAL CrewFile:Wing air flow pattern.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Wing_air_flow_pattern.jpg  License: Creative Commons Attribution-Sharealike 3.0  Contributors: UWALCrewFile:Oil flow vis on straight wing.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Oil_flow_vis_on_straight_wing.jpg  License: Creative Commons Attribution-Sharealike 3.0 Contributors: UWAL CrewFile:Fog visualization.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Fog_visualization.jpg  License: Creative Commons Attribution-Sharealike 3.0  Contributors: User:GeorgepehliImage:Vertical wind tunnel at TsAGI.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Vertical_wind_tunnel_at_TsAGI.jpg  License: Creative Commons Attribution-Sharealike 2.0 Contributors: Yuriy Lapitskiy (User:Yuriybrisk)

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