Author(s): Le Louvetel-Poilly Julie; Bigillon Fran Coise; Champagne Jean-Yves
Linked Author(s):
Keywords: Particle-laden flow; Wall turbulence; Particle Image Velocimetry
Abstract: Experiments have been performed in an open-channel flow to study the interaction between the turbulent structures of the wall and particle motion. Particle Image Velocimetry technique was used to simultaneously measure both the turbulent characteristics of the flow and particle motion. Thus, from these measurements it was possible to go into more detail for the turbulent structures involved in particle motion, in particular ejections and sweeps. The particles used in these experiments were ceramic beads of 0. 329 mm diameter, with a density of 3800kg/m3. Five hydraulic conditions have been tested, with Reynolds numbers varying from 3, 000 to 30, 000. Results concerning the turbulence of the flow and the motion of the beads were analyzed together. They show that the moving beads are located preferentially into sweeps and ejections with a Reynolds stress about 2 to 6 times stronger than the mean Reynolds stress. They also show that there is a strong correlation between the vertical motion of the beads and their surrounding turbulent structure, indicating that the ceramic beads move along with the turbulent structures.
Year: 2007