Streamlines can be visualised in steady flow in the wind tunnel by using fog, smoke or tufts. In this way, a clear impression of an instantaneous flow field can be presented and problematic flow areas, such as stall, can be shown.
The experimental unit is an open wind tunnel, in which streamlines, flow separation and turbulence can be made visible by using fog. The evaporated fog fluid is non-toxic, water soluble and the precipitate does not affect common materials. Precipitates can be easily wiped off with a cloth.
The air flow is generated by a fan. To achieve a low-turbulence flow, the air flows through a stabilisation chamber with a flow straightener. Fog is added to the flowing air through several nozzles. Then the air flows around or through a model in a experimental section and the flow field becomes visible. The experimental section has a black background and a sight window; additional lighting makes the streamlines clearly visible.
Four interchangeable models (cylinder, orifice plate, aerofoil and guide vane profile) are included. The aerofoil’s angle of attack is adjustable.
Learning Objectives & Experiments
- Visualisation of streamlines
- Flow around or through differently shaped models
- Flow separation and turbulence
- Stall as a function of the angle of attack
Specification
- Visualisation of streamlines flowing around and through different models
- Open wind tunnel with radial fan and a fog generator
- Operation with non-toxic and water-soluble fog fluid
- Illuminated experimental section with sight window and black background
- Low-turbulence flow through stabilisation chamber with flow straightener
- Distributor with nozzles for injecting the fog
- Four different models, angle of attack at aerofoil and guide vane profile adjustable
- Scale for displaying the angle of attack
Technical Specification
- Experimental section
- Transparent area: 252x252mm
- Cross-section: 252x42mm
- Aerofoil pivotable by 360°
- Models
- Cylinder: diameter: 60mm, height: 24,5mm
- Aerofoil: 15×24,5x100mm
- Guide vane profile: 20×24,5x100mm
- Orifice plate: 2x 25×24,5x10mm
- Orifice opening: 10mm
- Radial fan
- Max. Volumetric air flow rate: 480m3/h
- Max. Pressure difference: 300Pa
- Fog generator
- Power consumption: 700W
- 230V, 50Hz, 1 phase
- 230V, 60Hz, 1 phase
