wolfvierbergen
Open Wind Tunnel Design and Construction
An experimental project to design, build and test a functional open wind tunnel for aerodynamic testing and research.
The complete assembled wind tunnel
Read the original paper in dutch or the translated version*
More pictures can be found in the presentation
*Translation is done by Google Translate and contains errors.
Key Features
- Open-circuit design with 5.09:1 contraction ratio
- Maximum air speed of 33 km/h (9.2 m/s)
- Laminar flow generation capabilities
- Transparent test section for flow visualization
- Digital speed control system
Technical Design
The wind tunnel consists of six main components. From left to right:
1. Honeycomb Flow Straightener
- 6600 plastic straws arranged in a grid
- 6mm diameter, 60mm length
- Mounted at tunnel inlet
- Reduces lateral turbulence
2. Flow Conditioning Screens
- Two screens with 64% open area
- Nylon mesh construction
- 45mm spacing between screens
- Reduces axial turbulence
3. Contraction Section
- 5.09:1 contraction ratio
- Fifth-order polynomial curve profile
- Optimized for minimal flow separation
- MDF construction with external skeleton
4. Test Section
- Dimensions: 180mm × 190mm × 580mm
- Plexiglass windows for visualization
- Bottom access port for force measurements
5. Diffuser
- 9.9° expansion angle
- 574mm length
- Gradual velocity reduction
- Pressure recovery section
6. Drive System
- 4 × 210W brushless motors
- Three-blade propellers
- Electronic speed controllers
- Servo tester for power control
- 7.4V LiPo battery power source
Experimental Results
Airfoil Testing
Conducted comprehensive testing using NACA 4412 airfoil:
- Lift coefficient measurements
- Angle of attack comparison
- Speed dependency analysis
Key findings:
- Maximum lift achieved at 30° angle of attack
- Experimental results closely matched theoretical predictions
Technologies Used
- Fusion 360 for CAD design
- Laser cutting for precision components
- 3D printing for custom parts
- Pitot tube airspeed measurement
- Digital force measurement system
Testing Methods
- Air Speed Measurement
- Pitot tube system
- Fluid manometer measurement
- Multiple test points across section
- Speed range: 0-33 km/h
- Flow Quality Assessment
- Smoke visualization
- Flow uniformity testing
- Force Measurement
- Digital scale
- Multiple angle testing
Contributors
- Maarten Espeel
- Kobe Vlasselaer
- Wolf Vierbergen
Acknowledgments
Special thanks to:
- Ludo Verluyten (Mentor)
- Bike Valley Team
- Heilig-Hartinstituut Heverlee
Note: For detailed technical specifications, experimental procedures, and complete results, please refer to the full thesis document.