The UW Mixing Layer Tunnel (UW-MLT) is a low-speed, blower wind tunnel. The test section of the tunnel is 200 cm in length, 25 cm in height and 80 cm wide. The tunnel has full optical access through the sides and floor of the test section. The test section has an adjustable ceiling to allow a prescribed pressure gradient to be maintained along the length of the test section.The mean velocity in the wind tunnel is continuously-variable velocity up to a maximum freestream velocity of 33 m/s when operated without the mixing layer experiment. The flow is uniform across the span to within ±0.8% of the centerline velocity, and the freestream streamwise fluctuation intensity is less than 0.3%.For experiments requiring a mixing layer in the test section, a splitter plate is mounted in the conditioning section of the wind tunnel and divides the flow into equal sections upper and lower. The splitter plate ends at the entrance to the test section. A head loss device is mounted in the lower section, near the leading edge of the splitter plate and upstream of the beginning of the contraction. It consists of six layers of furnace filter material. The velocities of the high- and low-speed streams have been measured at 38 m/s (Uh) and 27 m/s (U¬l), respectively. These velocities give a velocity ratio of 0.71, a convection velocity of Uc = 32 m/s, and a characteristic velocity difference of Us = DðU = 11 m/s. Hot-wire measurements at the trailing edge of the splitter plate indicated that the boundary layer thicknesses on the high- and low-speed sides of the plate were 1.25 mm and 1.0 mm, respectively.
Located in EN L27 Point of Contact: Dr. Doug Smith