The Subsonic Wind Tunnel (14) is an open-circuit tunnel. It is operated by a 400 KW electric motor connected to a one-stage centrifugal fan. The control system of the fan permits to change its rotational speed continuously from 5 rpm to 645 rpm. As a result, the maximum air speed in the test section is about 90 m/sec (Reynolds Number – up to 6 ×106 /meter). The turbulence level is less than 0.5%. The 1m×1m test section is 3m long follows an inlet nozzle having a 25:1 contraction ratio. Eight screens mounted at the inlet entrance reduce the turbulence level and the effects of external wind fluctuations. The velocity range is between 0 and 90m/sec.
Below: Prof. Gil Iosilevskii inside the tunnel with a wing-suit: a final graduate project (details)