Abstract:
Laboratory experiments were conducted to investigate the hydraulic behaviour of plunging turbidity currents
in reservoirs. One-dimensional turbidity currents driven by uniform non-cohesive sediment (silica flour) were
generated in a 16.5m long, 0.3m wide and 0.75m high channel. Measurements of velocity profiles, suspended
sediment concentration profiles and grain size distributions provided important insights into the spatial evolution
of turbidity currents structure. The dimensional velocity profiles collapsed in a single curve confirming the
similarity to a wall jet velocity profile. Downstream the plunge region, the spanwise evolution of the mean
velocity profiles reveals that the point of maximum velocity increases gradually, approaching a constant value
of 30% of the current thickness, which corresponds to a fully developed wall region. The study also shows the
existence of a dimensional sediment concentration profile for each particle size.
