Aeroacoustic Wind Tunnel

The Aeroacoustic Wind Tunnel (AWT) is a unique test rig for the investigation of aeroacoustic phenomena in ducts and turbomachines. It was built and put into operation in 2012. The test rig allows high mass flow rates in conjunction with high pressures.

Field of Application

  • Investigation of aeroacoustic generation and transport mechanisms in circular ducts
  • Testing of acoustic duct liners
  • Testing and optimization of acoustic and aerodynamic instrumentation and sensors
  • Testing and validation of measurement techniques and analysis routines e.g. Radial Mode Analysis (RMA), Beamforming, etc.
  • Validation of numerical models (CAA)

Description

The test section can be replaced by different modules such as sound absorbers, instrumental test sections and even rotating turbine or compressor stages which can then be investigated under known inflow conditions.

The current project deals with the investigation of the acoustic transport mechanisms in tubes and turbomachines. An acoustic excitation system was implemented into the test section of the AWT which generates synthetic acoustic fields to facilitate this investigation. These acoustic fields are transported through the test section and cause varying acoustic pressure fields which are then measured in different positions. These measurements allow conclusions to be drawn about the transport mechanism.

The simple design, the high number in measurement positions and the well known acoustic and aerodynamic boundary conditions makes the AWT suitable for the validation of numerical models like CAA (Computational Aeroacoustics).

Fig. - General overview Aeroacoustic Wind Tunnel (AWT) Fig. - General overview Aeroacoustic Wind Tunnel (AWT) Fig. - General overview Aeroacoustic Wind Tunnel (AWT)
General overview Aeroacoustic Wind Tunnel (AWT)
Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units) Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units) Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units)
AWT with integrated sound generator (16 circumferentially distributed acoustic units)
Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units) Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units) Fig. - AWT with integrated sound generator (16 circumferentially distributed acoustic units)
AWT with integrated sound generator (16 circumferentially distributed acoustic units)

Measurement Techniques

  • Steady and unsteady pressure sensors
  • High-precision prepolarized pressure microphones
  • Temperature measurements using PT 100 and Type K sensors
  • Measurements of velocity components and turbulence using CTA/CCA Sensors
  • (endoscopic) 3-component Particle Image Velocimetry (PIV) for flow field measurements
  • Radial and circumferential traversing system for highly resolved acoustic measurements

Specifications

Mass Flow Rate 9,2 kg/s
Pressure Ratio 3,2
Diameter Test Section 0,5 m
Range in Reynolds Number 3,1x105 bis 1,2x106
Homogeneous, swirl-free inflow conditions
Low background noise
Acoustic excitation system with 16 azimuthally distributed speakers

Contact

Stefanie Lohse, M.Sc.
Research Staff
Address
An der Universität 1
30823 Garbsen
Building
Room
211
Stefanie Lohse, M.Sc.
Research Staff
Address
An der Universität 1
30823 Garbsen
Building
Room
211