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HM 170 OPEN WIND TUNNEL

Training at the HM 170 Open Wind Tunnel at the Technical College for Aeronautical Engineering in Hamburg (Germany)

Measuring lift and drag forces as a function of the angle of attack of an aerofoil with flap and slot

HM 170 Open WindTunnel at the Technical University of Wildau (Germany), Laboratory for Aeronautical Engineering

Measuring lift and drag forces and moment on the aerofoil drag body with the three-component force sensor

Measuring lift and drag forces on the streamlined body with the two-component force sensor

The NEW design of the open wind tunnel HM 170

Pressure distribution on an aerofoil under surrounding flow

GUNT offers an “Eiffel” type open wind tunnel as a classic experiment system in the field of flow around bodies.

The flow medium of air is brought up to the desired velocity by a fan and flows around the model being studied in a measuring section. Additional

experiments, such as investigation of the boundary layer or pressure distri-bution of drag bodies immersed in a flow are available as options.

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HM 170 SELECTED EXPERIMENTS

PRESSURE DISTRIBUTION AT THE PERIMETER OF A CYLINDER UNDER SURROUNDING FLOW

FLOW AROUND VARIOUS DRAG BODIES HM 170.01 – HM 170.11

DEMONSTRATION OF FLUTTER

Air flows along an elastic system which can be moved by motion-controlled flow forces in vibrations with significant amplitudes. This instability phenomenon is called flutter. Flutter is crucial in the design of aircraft, bridges, chimneys and high-voltage power lines. This model can be used to demonstrate the aerodynamic excitation of vibrations and instability. By using a stroboscope it is possible to observe the natural oscil-lation of the wing.

HM 170.23 Pressure Distribution on a Cylinder

record pressure distribution on the perimeter of the cylinder

measuring the static pressure

each pressure measurement point is equipped with a hose connection

1 measuring point, 2 flow separation, 3 turbulence Comparison between measured and theoretical pressure distribution whenflowing around a cylinderred theoretical pressure distribution, green measured pressure distribution

Force measure-ment on the drag body

FA lift force, FW drag

Flutter shown over time

In conjunction with the inclined tube manometer: Recording the pressure distribution by individual measurement at the pressure measurement points on the cylinder

In conjunction with the HM 170.50 16-Tube Manometers: Recording the pressure distribution

Particularly clear illustration of the pressure distribution by the simultaneous measurement of all pressure measuring points with the HM 170.50 16-Tube Manometers

determining drag and lift coefficients

two-component force sensor for measuring drag and lift forces included in HM 170

visualisation of streamlines by using fog

HM 170.20 Airfoil, Spring-Mounted

demonstrate flutter (self-excited vibrations)

natural oscillation behaviour can be influenced by different spring settings

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HM 170.22 Pressure Distribution on an AerofoilAerofoil profile NACA 0015length x width x height: 100x60x15mmItem No. 070.17022 recording the pressure curve measuring the lift force

additional aerofoil profiles available:HM 170.26 NACA 54118, LxWxH: 100x60x19,65mm, Item No. 070.17026HM 170.27 NACA 4415, LxWxH: 100x60x15,5mm, Item No. 070.17027

HM 170 ACCESSORIES FOR THE WIND TUNNEL

HM 170.01 Drag Body Spherediameter: 80mmItem No. 070.17001

HM 170.02Drag Body Hemispherediameter: 80mmItem No. 070.17002

HM 170.03Drag Body Circular Discdiameter: 80mmItem No. 070.17003

HM 170.04 Drag Body Circular Ringouter diameter: 113mminner diameter: 56,5mmItem No. 070.17004

HM 170.05Drag Body Square Platelength x width: 71x71mmItem No. 070.17005

HM 170.08Drag Body Streamlined Shapelength: 240mmdiameter: 50mmItem No. 070.17008

HM 170.09 Drag Body AerofoilAerofoil profile NACA 0015length x width x height: 100x100x15mm Item No. 070.17009

HM 170.10 Drag Body Paraboloidlength: 90mmdiameter: 80mmItem No. 070.17010

HM 170.11 Drag Body Concave Shapediameter x length 80x68,65mmItem No. 070.17011

HM 170.21 Aerofoil with Slat and Slot Flap Aerofoil profile NACA 0015 length x width x height: 100x100x15mmItem No. 070.17021

HM 170.23 Pressure Distribution on a Cylinderdiameter x height: 50x75,5mmItem No. 070.17023

HM 170.06Drag Body Flaglength x width: 100x50mmItem No. 070.17006

HM 170.07Drag Body Cylinderdiameter x height: 50x100mmItem No. 070.17007

HM 170.34 Tube for Static Pressurediameter x length: 4x360mm, 2 holes with inner diameter: 0,8mm, Item No. 070.17034

Measuring static pressure: 1 measuring point for static pressure

HM 170.25 Model “Bernoulli”Air inlet: 292mm, air outlet: 146mm, opening angle 52°, Pitotstatic tube: outer diameter: 4mm Item No. 070.17025

horizontally movable Pitotstatic tube wedge-shaped inserts forming a measuring section

whose cross-section steadily narrows

Measuring pressures:1 stagnation point at the Pitotstatic tube (total pressure), 2 measuring point for static pressure, 3 inclined tube manometer from HM 170 displays the dynamic pressure

HM 170.28 Wake MeasurementCylinder: diameter x height: 20x100mmWake rake consists of 15 Pitot tubes, outer diameter: 2mm, distance between the Pitot tubes: 3mmItem No. 070.17028

it is possible to display the measured values on the PC using HM 170.55 Electronic Pressure Measurement

Measuring pressures: 1 stagnation point at the Pitot tube (total pressure), 2 cylinder, 3 measuring point for static pressure, 4 HM 170.50 16-Tube Manometers displays the dynamic pressure

HM 170.31 Pitot Tubeouter diameter: 4mmItem No. 070.17031

HM 170.32 Pitot Tube, Smallouter diameter: 2mmItem No. 070.17032

Determining the total pressure 1 stagnation pointThe pressure in the stagnation point is equal to the total pressure

HM 170.33 Pitotstatic Tube outer diameter: 3mmItem No. 070.17033

Measuring the dynamic pressure: 1 stagnation point, 2 measuring point for static pressureThe difference between total and static pressure gives the dynamic pressure

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HM 170 ACCESSORIES FOR THE WIND TUNNEL

HM 170.24 Boundary Layer Analysis with Pitot Tube2 plates, rough and smooth, LxWxH=279x250x3mmItem No. 070.17024

vertically movable Pitot tube measures the pressures at various distances from the plate surface horizontally movable plate for recording pressures

along the flow displaying measured values on the PC using

HM 170.60 System for Data Acquisition and HM 170.61 Electronic Displacement Measurement

Measuring pressures:1 stagnation point at the Pitot tube (total pressure), 2 flat plate, 3 boundary layer, 4 measuring point for static pressure, 5 16-tube manometers from HM 170 displays the dynamic pressure

HM 170.40 Three-Component Force SensorLxWxH: 370x315x160mm (measuring amplifier)diameter x height: 115x150mm (force sensor)Item No. 070.17040

measuring amplifier with connections for forces and moment connection to HM 170.60 possible display of drag, lift and moment

Measuring ranges drag: -4...+4N lift: -4...+4N torque: -0,5...+0,5Nm

1 force sensor, 2 measuring amplifier

HM 170.61 Electronic Displacement MeasurementItem No. 070.17061

optional accessories for HM 170.24 Boundary Layer Analysis with Pitot Tube displaying measured values on the PC using the

HM 170.60 System for Data Acquisition

Measuring rangeDisplacement: 0…10mm

HM 170.20 Airfoil, Spring-MountedAerofoil profile NACA 0015LxWxH: 200x100x15mmItem No. 070.17020

transverse rigidity: 216N/m torsion rigidity: 0,07..0,28Nm/rad

HM 170.55 Electronic Pressure Measurement 0...500PaLxWxH: 370x315x160mmItem No. 070.17055

18 inputs, 0...500Pa CD with GUNT software included data acquisition via USB under Windows Vista

or Windows 7

HM 170.60 System for Data AcquisitionLxWxH: 370x315x160mm (interface module)Item No. 070.17060

CD with GUNT software included data acquisition via USB under Windows Vista

or Windows 7 angle sensor

Measuring ranges displacement: 0…10mm angle: 0…360° pressure: 0…10mbar velocity: 0…48m/s force

drag: -5...+5Nlift: -5...+5Nmoment: -0,5...+0,5Nm (for HM 170.40 Three-Component Force Sensor)

HM 170.52 Fog GeneratorLxWxH: 370x315x160mm (supply unit)Power consumption: 500WItem No. 070.17052

HM 170.50 16-Tube ManometersLxWxH: 670x215x745mmItem No. 070.17050

pivoted, inclination stages: 1:1, 2:1, 5:1, 10:1 max. 600mmWC height-adjustable manometer individual zero points can be set

The tube manometer operates on the principle ofcommunicating tubes

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2

pressure drag, lift force,

moment (only with HM 170.40)

displacement/ angle

velocity

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