Different types of measuring techniques are applied in the laboratory. The measured quantities ranges from global aerodynamic forces up to unsteady velocity fields.
Aerodynamic forces and moments on a model are measured using an in-house aerodynamic balance (3 force components) or commercial sensors from ATI (6-components : 3 forces – 3 moments). For this type of measurement, the load sensor is located inside or as close as possible of the model.
Characterisation of the turbulent content of the flow is performed by Cobra probe measurements (from the company Turbulent Flow Instrumentation). The three components of the flow velocity are measured simultaneously up to 2kHz.
Hot wire anemometry
Velocity components are measured at distinct location of interest of the flow field using hot wire probes (from the company Dantec Dynamic). Despite the intrusive nature of the probe in the flow and its low spatial resolution, this technique has a very good temporal resolution (several kHz) that enables to study the frequency content of unsteady flow fields (turbulent content, vortex shedding).
Aerodynamic pressure surfaces are measured by pressure scanners, located inside the model and connected to the pressure taps by vinyl tubes. This measurement technique enables to acquire unsteady pressure distributions at 100-200 locations with a rate of 1/500 sec. Adapted corrections are applied to take into account the effect of the pneumatic line (tube) between the pressure taps and the sensor.
The laboratory owns :
- A Dynamic Pressure Measurement System (DPMS, from the company Turbulent Flow Instrumentation) with 128 pressure taps in the range [0-2500] Pa.
- Two pressure scanners from PSI (Measurement Specialities): HD32 (FS +/- 5PSI) and HD64 (FS +/- 1PSI).
Particle Image Velocimetry
Unsteady velocity fields are measured by Particle Image Velocimetry (PIV). This technique is based on the synchronisation of a high speed camera and a double pulse laser. The PIV system available at the laboratory (from the Dantec company) enables to visualise a 2D unsteady flow field of 12cm x 12cm window at a rate of 1kHz.
Accelerometers and lasers
The flow induced vibrations can be measured with accelerometers placed on the structure or laser, with no contact on the latter. In addition the Wind Tunnel Laboratory uses wireless small size accelerometers developed at the microsys laboratory of the University of Liège.
The complete technical description of the facility and the available measurement equipments can be downloaded here:
Feel free to contact us if you need more information.