Velocity and particle-flux characteristics of turbulent particle-laden jets

The velocity and mass flux characteristics in the non-self-similar region of a round turbulent bead-laden jet for three bead diameters (200, 80, and 40 microns), at two mass loadings, are described. The mean velocity of the 200-micron beads is virtually constant, with little influence of mass loading on the mean motion of the beads because the mean Stokes number is small. The centerline velocity of the 80-micron beads decays but not as a function of mass loading, at least up to 86 percent (mass/mass). For the 40-micron beads, the rate of decay of the centerline bead velocity decreases with increasing mass loading. The rate of spreading of 40-micron beads decreases with increasing loading, but the opposite is true for the 80-micron beads. The 'fan-spreading' model for the motion of the beads is considered, which refers to quasi-unidirectional trajectories of the beads from the exit of the jet up to about 20 diameters downstream for the 40-micron diameter beads, and farther for the larger beads.