High-Resolution Analysis of Particle Deposition and Resuspension in Turbulent Channel Flow

Figures & data

FIG. 1. Particle resuspension caused by collision with airborne particles.

FIG. 2. Experimental setup.

FIG. 3. Details of the rectangular channel.

FIG. 4. Number-based particle size distributions of Powders A and B.

TABLE 1 Properties of the two types of alumina powders

Sample	Dp50 (µm)	σg (−)	(µm)	ρp (kg m^−3)	Shape
Powder A	3.1	1.5	3.4	3900	Spherical
Powder B	4.3	1.4	4.6	4000	Irregular

^a D_p50: number median of projected area diameter of particles.

^b σ_g: geometric standard deviation of projected area diameter.

^c : number average particle diameter (= D_p50 exp (0.5 ln²σ_g)).

FIG. 5. Image of particles deposited on the glass side wall (Powder A).

TABLE 2 Detailed flow conditions in the channel

u (m s^−1)	Re (–)	I (–)	u* (m s^−1)	urms (m s^−1)
10	3100	0.059	0.73	0.59
20	6200	0.054	1.34	1.08

FIG. 6 Particles trajectories during the deposition and resuspension processes (Powder B, u = 20 m s⁻¹, interval of open symbols: 11.4 ms, the values of residence time are shown in parentheses).

FIG. 7. Particle velocities during the deposition and resuspension processes (Powder B, u = 20 m s⁻¹).

FIG. 8. Particle deposition and resuspension fluxes as a function of time (Powder A, u = 10 m s⁻¹).

FIG. 9. Normalized autocorrelation functions for the particle deposition and resuspension processes (Powder A, u = 10 m s⁻¹).

FIG. 10. Normalized cross-correlation between particle deposition and resuspension (Powder A, u = 10 m s⁻¹).

FIG. 11. Cumulative distribution of the residence time of particles on the surface (Powder A, u = 10 m s⁻¹).

FIG. 12. Relationship between residence time and particle diameter (Powder A, u = 10 m s⁻¹).