Numerical Simulation of Gas-Particle Two-Phase …
471
Fig. 2 Geometry and mesh, a smelting shaft geometry 1—Nozzle; 2—Shaft; 3—Gas space; 4—
melting surface; 5—uptake shaft, b mesh
conservation equations, momentum balance equations, and chemical composition
equations. These equations can be used in the following general forms:
∂ρϕ
∂t
+
∂
∂ x i
(ρϕu i ) =
∂
∂ x i
Γ ϕ
∂ϕ
∂ x i
+ S ϕ + S pϕ
ρ is the density of the fluid; t is the time;
u i is the velocity in the direction I;
ϕ is the universal variable;
u i is the viscosity;
ϕ is the index of the transport process.
(2) Discrete phase model
The particle motion uses the discrete phase model (DPM) to track, and the governing
equation can be showed as follows:
dν p
dt
= F D (ν g − ν p ) +
g(ρ p − ρ g )
ρ p
+ F
ν
is the velocity vector;
g
gravity acceleration;
F
depicts the other force exerted on the particle;
F D (ν − ν p ) is the drag force.
(3) Chemical reactions
The flash smelting raw material has complex species in it. As shown in Table 1, the
species mass fractions were listed. The major reactions considered in the simulation
are listed in Table 2.