The carousel (or annular flume) consists of a circular channel with a mean diameter of 2.1 m and a channel width of 0.2 m. The water depth is 0.3 m. A circular lid at the surface drives the water. In order to minimise the effect of secondary currents near the bottom the channel itself is rotated in the opposite direction. The operational speeds of the lid and the channel are experimentally determined using small spheres with a density slightly larger than that of the water. Furthermore, velocities above the bottom were measured with an electromagnetic current meter. The optimal ratio of the angular velocities of the upper lid and the channel is also a function of the water depth.

The sampling of sediments as well as the rotational speeds of the lid and the channel are controlled by a personal computer. A sampling frequency of 1/30 Hz is chosen. Data are transmitted between the rotating flume and the personal computer with the aid of an infra-red transmitter and receiver.

The annular flume is located inside a climate controlled room. A temperature varying between 20.1°C and 20.3°C and a humidity ranging between 70% and 80% guarantees almost constant test conditions.