Anechoic wind tunnel

More Information

About the Anechoic wind tunnel

The anechoic wind tunnel (AWT) is an acoustic tunnel capable of testing velocities of up to 80 metres per second (m/s). It can be used in two different configurations: open jet and a Kevlar test section.

The tunnel is regularly used by undergraduates, university researchers and commercial clients to undertake a wide variety of aerodynamic and acoustic tests across numerous industries. Typical aerospace applications include aerodynamic and aeroacoustic testing of aircraft components, including wings, landing gear and other sources of aerodynamic noise.

The anechoic wind tunnel at Boldrewood Campus is part of the National Wind Tunnel Facility.

The test section is 1.0 metres (m) wide by 0.75 m tall with a maximum flow speed of 80 m/s. It has far field microphones and phased microphone array.

Take a virtual tour around anechoic wind tunnel.

Technical specification

closed circuit wind tunnel
test section 1.0 metres (m) × 0.75 m
test velocity 80 metres per second (m/s)
ducted silencers to minimise background noise
anechoic chamber (size 8.1 m × 5.1 m × 4.3 m) fitted with acoustic wedges
anechoic to a nominal frequency of 250 Hertz (Hz)
two test section configurations depending on application: open jet and Kevlar test section

Load cell for force measurements

ATI Delta SI-330-30 6-component loadcell

Microphones

16 ¼ inch GRAS 46E microphones
freefield - up to 80 kHz
16 ½ inch GRAS 46AE microphones
freefield - up to 20 kHz
¼ inch GRAS 47BX microphones
flush mounted - up to 70 kHz

Phased microphone arrays

77 channel phased microphone array, size 0.7 m x 0.7 m
112 channel phased microphone array, size 1.2 m x 1.2 m

Anechoic chamber

chamber wall thickness of 250 mm of reinforced concrete
the chamber is isolated from the base build floor slab via acoustic isolation pads
wedges create an anechoic environment to a nominal frequency of 250 Hz
acoustic panelling to minimise reflections from wind tunnel steel ducting

Performance

Mach number: 0.23
maximum flow speed: 80 m/s
Reynolds no: 5.4 x 10⁶/m
total pressure: 1.04 bars
pressure: up to 3.9 kilonewtons per square meter (kN/m²)
temperature: ambient to 296 Kelvin (K) (equal to 22.85 °C (73.13 °F))
run time: continuous

Testing capabilities

acoustic: farfield microphones and phased microphone array
flow visualisation: video, surface fluorescent oil flow
aerodynamic loads: capability to measure surface pressures and loads
laser measurements: capability to perform particle image velocimetry measurements
flow visualisation: video, surface fluorescent oil flow