Particle Levitation Due to a Uniformly Descending Flat Object

Figures & data

FIG. 1 Problem schematic.

FIG. 2 Sample solutions of equation (15) for r = 0.06 m and W = 0.5 m/s.

TABLE 1 Coefficients a _jk in Equation (18)

	k
j	1	2	3	4	5	6
0	4.660	−3.260	11.716	−38.696	38.388	−12.821
1	1.199	−2.002	−10.560	31.029	−28.924	9.267
2	0.034	−0.867	3.877	−6.834	5.390	−1.600

FIG. 3 Forces acting on an attached particle in shear flow.

FIG. 4 Critical friction velocity for particle detachment (0 to 5000 m/s² acceleration).

FIG. 5 Particle trajectories (2300 kg/m³ PM in air; disk velocity = 0.5 m/s).

FIG. 6 Particle trajectories (1000 kg/m³ PM in air; disk velocity = 0.1 m/s).

FIG. 7 Snapshots of the velocity magnitude (disk velocity = 0.5 m/s).

FIG. 8 Snapshot of the velocity field at h = 0.5 mm (disk velocity = 0.5 m/s).

FIG. 9 Stream-function evolution after disk is suddenly stopped at h = 0.5 mm.

FIG. 10 Minimum particle size to detach outside disk gap (R = 75 mm; W = 0.5 m/s).