LMFL Boundary Layer Wind Tunnel France

Facility and equipment


The facility is unique in Europe in terms of size and Reynolds number and in terms of the optical measurement technology developed around it.

  • High Reynolds number turbulent boundary layer at large scale;
  • Flow resolvable over all scales by current measurement technology;
  • Advanced Stereo and Tomo PIV expertise of the operating team;
  • Both flat plate, favorable and adverse pressure gradient boundary layer available;
  • Study of boundary layer separation possible.

The facility provides the following measurement equipment for use with the facility:

  • Single and x wire anemometry (IFA300, 8 channels anemometer) with traversing system, fully automatized and coupled to the regulation of the velocity and temperature of the wind tunnel to ensure accurate measurement;
  • Three high sensitivity microphones from B&K, conditioning electronics and data acquisition system;
  • Two stereoscopic PIV systems based on 2560×2160 sCMOS PCO cameras at 25Hz and a BMI 4-cavities laser (4x200mJ/pulse) or Innolas laser (2x150mJ/pulse);
  • Two stereoscopic PIV systems based on 2048×2048 Hamamatsu cameras at 4Hz;
  • One tomographic PIV system based on 5 PCO sCMOS cameras (2560×2160) at 25 Hz
  • One high repetition Stereo PIV system based on Quantronix Darwin Duo Laser (2x25mJ, 100W) and 2 Miro M340 cameras (2560x1600 resolution at 800 Images/s) that can be extended to Tomo-PIV using 2 Phantom V9 cameras (1600×1200) at 1000 image/s.

LML (LMFL Boundary Layer Wind Tunnel)

The present characteristics of the facility are:

  • Free stream velocity 3 to 10 m/s
  • Maximum boundary layer thickness 30 cm
  • Reynolds number range 8 000 to 20 000 based on momentum thickness.

The wind tunnel test section has recently been renewed thanks to the financial support of CNRS, the Regional Council and the FEDER European funding, through the CISIT research project. This test section is now fully transparent on 20 m long. The velocity is regulated better than 0.5% and the temperature better than 0.15 C.


Wind tunnel side view
Wind tunnel top view


Different models are available to allow studies on boundary layers under pressure gradient. Multiple hot wire anemometry, hot wire rakes, stereo and Tomo PIV, standard and high repetition PIV have been used extensively in this facility thanks to its unique optical accessibility.

Mean velocity profiles
Photos of the new test section of the wind tunnel