Bedform development in recirculating flume
Experiments were performed in the Tilting Bed Flume at the St. Anthony Falls Laboratory at the University of Minnesota (information here: http://www.safl.umn.edu/facilities/flumes-and-channels)
The experiments were meant to reproduce the steady-state development of river bedforms, with sediment recirculating in the flume (but water was not recirculating). To execute this condition, the following setup was deployed. All equipment locations are described in terms of longitudinal distance as measured by the data acquistion carriage.
x = 0.06 m - Upstream wall of flume - Water enters here via pipe connected to river supply. Discharge controlled by opening and closing valve. Discharge is determined based on calibration curve tied to valve values.
x = 0.36 m - Manifold discharging sediment from recirculation
x = 0.46-0.70 m - Baffles (array of vertical PVC pipes) to reduce turbulence
x = 0.77-1.68 m - Flow smoothener (piece of foam) floating on water surface to reduce water surface turbulence
x = 4.0 m - ADV to measure flow turbulence
x = 5.0 m - Beginning of test section for bedform observation
x = 13.0 m - End of test section for bedform observation
x = 13.51 m - Downstream wall to maintain sediment bed - height = 20 cm
x = 13.75 - 14.66 m - Funnel to collect sediment for recirculation
x = 14.9 m - Tailgate to control water depth