Large-scale anechoic continuous low-speed wind tunnel, 2m or 3m open-jet test section
Heated nozzle jet noise testing

Facility description

CEPRA19 is an open circuit wind tunnel with the following major components :

  • A 9 x 9 m inlet featuring a dust filter, acoustic baffles, anti-turbulence screens and a honeycomb,
  • A contraction with an inlet diameter of 9 m and two exit diameter: 3 m or 2 m,
  • A 9.6 m radius anechoic chamber (quarter of a sphere),
  • An acoustically treated flow collector,
  • A diffuser,
  • A fan silencer with two stages of acoustic baffles,
  • A centrifugal fan driven by a 7 MW asynchronous electric motor.


  • High quality continuous airflow at Mach number up to 0.38 or 0.18 respectively with 2m or 3m diameter convergent nozzle,
  • Very good anechoicity and low background noise in the 200 Hz to 80 kHz frequency bandwidth,
  • Nozzle model with bypass duct up to 265 mm, with a continuous total massflow up to 12 kg/s at 500 kPa,
  • Nozzle primary jet temperature up to 1150 K supplied by a 2 MW propane burner,
  • Nozzle secondary jet temperature up to 450 K (heat from compression alone),
  • Nozzle operating conditions are measured with an instrumented rig at the tip of the nozzle rig,
  • A 2-axis remotely controlled table is dedicated to adjustement of the airframe positionning relative to the nozzle model during opaerating (controlled with Model Deformation Measurement technique),
  • A 3-axis remotely controlled table allows displacement of instrumentation (acoustic antenna, PIV set-up, flow survey device ...).
Isolated nozzle test
Isolated nozzle test with far field microphones measurement
Installed nozzle test
Installed nozzle test with acoustic antenna measurement

Typical tests

Airframe noise test with acoustic antenna measurement
Airframe noise test
with acoustic antenna measurement
  • Jet noise (hot or cold) with both isolated and installed configurations.
  • Airframe noise (High lift Devices noise, landing gear noise ...).
  • Noise reduction using micro jet simulator,
  • Fan noise using TPS with both isolated and installed configurations,
  • Industrial aeroacoustics issues.

Measurement techniques

  • Far-field microphones measurements with two 6m radius arcs fitted with 12 microphones each, flyover (horizontal plane crossing jet axis) and sideline (longitudinal plane inclined of 56° over the flyover arc plane),
  • Acoustic antenna measurements (linear or 2D antenna) for source location,
  • Flow survey using probes (five-holes, pressure, temperature),
  • 3-component Particle Image Velocimetry (PIV) measurements in longitudinal or transverse planes with air flow and jet flow seeding,
  • Visualization by coloured oils.
Typical PIV set-up
Typical PIV set-up
Flow survey and coloured oils visualization
Flow survey and coloured oils visualization


Secure test preparation and testing sites with card access, data and computer firewalls.


Technical documentation