Experiment 1To perform the study of an Educational Wind Tunnel.

Apparatus Educational Wind TunnelIntroductionWind tunnel actually is the classic experiment system for aerodynamic flow experiments. The model being studied remains at rest while the flow medium is set in motion, and thus the desired flow around the model is generated.Gas Dynamics laboratory is equipped with an educational yet relatively modern wind tunnel to simulate real flight conditions on a smaller scale. Although all the flight conditions cannot be simulated in this tunnel but its found well in case of smaller airfoils or components.Our laboratory contains an HM170 Educational Wind Tunnel manufactured by GUNT. It is an "Eiffel" type open wind tunnel used to demonstrate and measure the aerodynamic properties of various models. For this purpose, air is drawn in from the environment and accelerated. The air flows around a model, such as an aerofoil, in a measurement section. The air is then decelerated in a diffuser and pumped back into the open by a fan.Parts of Wind Tunnel1. Inlet contour2. Flow straightener3. Nozzle4. Measurement section5. Drag body6. Force sensor7. Control unit8. Diffuser9. Switch cabinet10. Manometer11. Axial fanDescription of core parts of Wind Tunnel1. Intel contourInlet contour is basically the contraction section of this wind tunnel. It is a carefully designed nozzle contour and air actually enters the system through this section.2. Flow straightenerIt is a honeycomb mesh which ensures the uniform velocity distribution with little turbulence into the closed measurement section through a nozzle.3. NozzleA converging nozzle is installed right after the flow straightener which increases the speed of the air flow while not disturbing its uniform velocity distribution.4. Measurement sectionAny component or part which is required to be analyzed aerodynamically is fixed in this section and its behavior under the influence of drag is carefully examined in here.5. Force sensorIt is an electric sensor used to determine the force being exerted on the body under the influence of drag.6. Display and control unitWind tunnel is controlled through this unit. For example speed of air flow inside the tunnel is displayed and/or controlled through this unit.7. DiffuserIt actually is a diverging nozzle section which greatly reduces the speed of air after the measurement section.8. Axial fanIt is a single-phase (220 VAC) electric fan with blades in such an orientation that the flow through this, is parallel to the axis of rotation of this fan.Specifications of Wind TunnelFlow cross section in measurement section (W x H)292 x 292 mm

Flow cross section length420 mm

Wind velocity range3.1 to 28 ms-1

Electric power consumption2.55 kW

Force measuring range (x2)0 to 10 N

Pressure measuring range0 to 5 mbar

L x W x H2860 x 860 x 1700 mm

Weight (approx.)250 kg

Electric connection230 VAC/50 Hz/1-phase

Classification of Wind Tunnels Low-speed wind tunnel (M < 1) High-speed wind tunnel (M = 1) Supersonic wind tunnel(M > 1) Hypersonic wind tunnel(M > 3) Subsonic wind tunnel (0.3 < M < 1) Transonic wind tunnel (0.75 < M