4' wide x 96" long flume
The AUR flume was designed and constructed at the AUR laboratory in Radford, Virginia. The two straight sections are joined on the ends by two semicircular annuli of mean radius 2.5 feet. The straight plexiglass test section is 8' long and 4' wide. The gravel tank in the test section is 46" wide, 50" long, and 9" deep. The gravel of various sizes with a specific gravity of 2.5 to 3 have been used. The top flume speed is above the incipient scour speed. Active flow control systems (suction and injection) are used to produce a span-wise uniform boundary layer flow upstream of the test section. AUR, Inc (NCHRP-IDEA Project 162 Report) and Sheppard et al.(NCHRP Report 682) show that if a hydraulic structure does not scour at model scale, it will not scour at full scale.
Many researchers have conducted experiments in laboratory flumes to investigate the local scour depth around a circular pier. The following flume test video in the AUR Flume Facility shows removal of sediment around a circular bridge pier by the primary horseshoe vortex and shedding vortices.