Numerical Simulation of Gas–Liquid Flow …
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Table 1 Bottom blowing simulated boundary conditions
Phase
Parameter
Unit
Number
Matte
Density
kg/m 3
5075
Viscosity
kg/m s
2.5 × 10 −3
Surface tension
N/m
0.33
Slag
Density
kg/m 3
3200
Viscosity
kg/m s
0.2
Surface tension
N/m
3.17 × 10 −4
Oxygen-enriched air
Density
kg/m 3
1.27
Viscosity
kg/m s
1.982 × 10 −5
Mathematical Model
Model Assumptions
Without affecting the results, and in order to speed up the calculation process, it is necessary to rationally simplify the actual bottom blowing model and set up hypothetical
conditions, as follows:
(1) The interface between gas and liquid is a free surface.
(2) Initialize the uniform temperature distribution in the molten bath, without considering the influence of chemical reaction and temperature field on the physical
properties of the molten bath.
(3) The initial height of molten bath is 2.5 m, ignoring the influence of feeding and
discharging on the height of molten bath.
(4) The wall is considered a non-slip boundary, and the standard wall function is
used to deal with the boundary layer near the wall.
Numerical Calculation Model
VOF Model
The VOF model is typically used to simulate a variety of non-mixable fluids, so it is
mainly used to simulate the gas–liquid mixing process in this simulation, including
stratified flow and free surface flow. VOF model assumes that the multiphase fluid
does not exist between each other throughout; in the model every phase, you need to
introduce a phase volume fraction in each control volume, all phase volume fraction
and 1 in the control volume, if the volume fraction of the q phase fluid for α, then it
will be there are three possibilities:
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Table 1 Bottom blowing simulated boundary conditions
Phase
Parameter
Unit
Number
Matte
Density
kg/m 3
5075
Viscosity
kg/m s
2.5 × 10 −3
Surface tension
N/m
0.33
Slag
Density
kg/m 3
3200
Viscosity
kg/m s
0.2
Surface tension
N/m
3.17 × 10 −4
Oxygen-enriched air
Density
kg/m 3
1.27
Viscosity
kg/m s
1.982 × 10 −5
Mathematical Model
Model Assumptions
Without affecting the results, and in order to speed up the calculation process, it is necessary to rationally simplify the actual bottom blowing model and set up hypothetical
conditions, as follows:
(1) The interface between gas and liquid is a free surface.
(2) Initialize the uniform temperature distribution in the molten bath, without considering the influence of chemical reaction and temperature field on the physical
properties of the molten bath.
(3) The initial height of molten bath is 2.5 m, ignoring the influence of feeding and
discharging on the height of molten bath.
(4) The wall is considered a non-slip boundary, and the standard wall function is
used to deal with the boundary layer near the wall.
Numerical Calculation Model
VOF Model
The VOF model is typically used to simulate a variety of non-mixable fluids, so it is
mainly used to simulate the gas–liquid mixing process in this simulation, including
stratified flow and free surface flow. VOF model assumes that the multiphase fluid
does not exist between each other throughout; in the model every phase, you need to
introduce a phase volume fraction in each control volume, all phase volume fraction
and 1 in the control volume, if the volume fraction of the q phase fluid for α, then it
will be there are three possibilities: