Experimental Investigation of the Effect of Inlet Concentration on the Behavior of Turbidity Currents in the Presence of Two Consecutive Obstacles

Abstract

Turbidity currents are often the main processes of sediment transport in deep waters and reservoirs. To prevent sedimentation in critical locations, various methods, such as placing solid obstacles in the path of these flows, have been proposed. In the present study, the effect of inlet concentration on the behavior of turbidity currents in the presence of two consecutive triangular obstacles was investigated experimentally. For this purpose, a series of laboratory experiments were conducted with various inlet concentrations. In each experiment, velocity and concentration profiles were measured using an acoustic Doppler velocimeter. The velocity of the current head and local Froude number were also determined along the test channel. The results show that a region with negligible velocity and a notable concentration develops upstream of each obstacle, and as the inlet concentration increases, this region becomes larger. In addition, the results also indicate that the sediment deposition rate is higher upstream of the first obstacle compared to that of the second obstacle. Furthermore, observations show that three recirculation regions are developed between the obstacles.