Closed Circuit Subsonic Wind Tunnels
The tunnel circuit also includes a diffuser and round to square transition sections upstream and downstream of the axial fan which is connected to the main structure through flexible sleeves. The test sections are generally constructed in plexiglas for full flow visualization, and to permit the use of laser anemometry systems.  The plexiglas test section dimensions are 300 x 200 mm, and the length 600 mm. Aerofoils and other models, together with a balance, can be mounted through the top panel. Passages for probes (pitot tubes, hot wires,…) are located on the front side panel. The wind-tunnel is of compact design. It can be used for fundamental experiments in aerodynamics.The corner sections are fitted with guide vanes to avoid separation and to maintain a satisfactory pressure distribution irrespective of changes in flow direction.The contractions are designed to give an optimum velocity distribution in the test section. Models, aerofoils, balances and probes can be fitted to the test sections, together with single or multi-axis probe traversing systems. The contractions are designed to give an optimum velocity distribution in the test section.

Technical specifications:-
•  Uniform velocity distribution in the test section.
•  Turbulence level: < 0.5 % at 40 m/s.
•  Overall dimensions: 4420 x 1420 x 2100 mm.
•  Test section dimensions: section : 300 x 300 mm, length: 700 mm.
•  Contraction ratio: 8.
•  Velocity range: 2 to 40 m/s.
•  Power requirement: 7,5 kW.
•  Weight (approx.): 450 kg.
•  Overall dimensions: 3000 x 700 x 1500 mm.
•  Test section dimensions: section : 300 x 200 mm, length : 600 mm.
•  Contraction ratio: 4.
•  Velocity range: 2 to 40 m/s.
•  Uniform velocity distribution in the test section.
•  Turbulence level: < 0.8 % at 40 m/s.
•  Weight (approx.): 250 kg.
•  Power requirement: 3 kW.

Closed Circuit Subsonic Wind Tunnels