Table 1. Physical Parameters.

Numerical parameter	Values
fluid density, ρf (kg·m–3)	1.225
fluid viscosity, ν (Pa·s)	1.8 × 10–5
local fluid velocity at the inlet, U (m·s–1)	9
particle diameter, dp (μm)	2, 5, 10, 20
particle density, ρp (kg·m–3)	2,500, 5,000, 7,500, 10,000
Poisson’s ratio, υ	0.21
surface energy, γ (J·m–2)	0.01, 0.1, 1
shear modulus, G (Pa)	1 × 108
coefficient of restitution, e	0.5
coefficient of static friction	0.5
coefficient of rolling friction	0.01
time step, (Δtf, Δtp) (s)	3 × 10–7, 3 × 10–9