2008 Volume 52 Pages 733-738
Transport mechanism of suspended sediment is one of great interests in river engineering, because there are complicated interactions among flow structure, particle motion and bed forms. A lot of previous studies have been conducted on velocity measurements and numerical simulations in these suspended sediment flows. However, there are still many uncertainty about turbulence modulation, that is to say, the particle effects on flow structure. In order to reveal this significant topic, we conducted simultaneous measurements of fluid velocity, particle velocity and sediment concentration by using a discriminator particle tracking velocimetory (D-PTV) and a discriminator particle image velocimetory (D-PIV).
It was found from the present study that the larger sediment particles enhance the turbulence intensities and Reynolds stress, while the smaller size particles depress them. Furthermore, we also revealed that this tendency becomes more remarkable as the sediment concentration is larger.
