Effect of Bottom Blowing Mode on Fluid Flow and Mixing Behavior in Converter
Abstract
:1. Introduction
2. Hydraulic Model
2.1. Experimental Principle
2.2. Experimental Setup and Method
2.3. Bottom Blowing Mode
3. Numerical Model
3.1. Modeling Assumptions
- (1)
- Air is treated as a compressible Newtonian fluid, water is treated as an incompressible Newtonian fluid, and the other fluid physical parameters are constants.
- (2)
- The flow in the model is isothermal.
- (3)
- The model calculation is a three-dimensional, full-scale, transient process.
3.2. Governing Equations and Turbulent Model
3.3. Solution Procedure
4. Results and Discussion
4.1. Model Validation
4.2. Comparison of Flow Field between Bottom blowing and Combined Blowing Conditions
4.3. Flow Characteristics of Molten Bath
4.4. Mixing Characteristics of Molten Bath
4.5. Abrasion Characteristics of Refractory Lining
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Nomenclature
Symbol | Description |
Fr’m, Fr’p | Modified Froude number of model and prototype |
u | Velocity of gas, m·s−1 |
g | Gravitational acceleration, m·s−2 |
d | Geometric feature size, m |
dt | Throat diameter of the Laval nozzle, mm |
de | Outlet diameter of the Laval nozzle, mm |
P0 | Stagnation pressure of the Laval nozzle, atm |
u0 | Outlet velocity of the Laval nozzle, m·s−1 |
c | Velocity of sound, m·s−1 |
Velocity vector of the fluid | |
P | Static pressure of the fluid, MPa |
fσ | Surface tension of the fluid, N·m−3 |
Y | Mass fraction of the species |
J | Diffusion flux of the species |
K | Turbulent kinetic energy, m2·s−2 |
Gk | Turbulent kinetic energy generated by the average velocity gradient, kg·m−1·s−3 |
Gb | Turbulent kinetic energy generated by the buoyancy, kg·m−1·s−3 |
YM | Turbulent dissipation rate generated by compressible turbulent pulsation, kg·m−1·s−3 |
C3ε, σk, σε and Cμ | Empirical constants [42], and their respective values are 1.44, 1.92, 0.8, 1.0, 1.3, and 0.09 |
A | Area of the wall surface, m2 |
Greek symbols | |
ρg, ρl | Densities of gas and liquid, kg·m−3 |
μ | Dynamic viscosity of the fluid, Pa·s |
α | Phase volume fraction |
Viscous stress term of the fluid | |
ε | Turbulent energy dissipation rate, m2·s−3 |
τ | Shear stress, Pa |
Subscripts | |
g, l | Gas and liquid phases |
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Items | Prototype | Model |
---|---|---|
Similarity ratio | 6 | 1 |
Bath diameter (mm) | 4382 | 730.33 |
Bath depth (mm) | 1360 | 226.67 |
Laval nozzle throat diameter (mm) | 38.4 | 6.40 |
Laval nozzle exit diameter (mm) | 49.9 | 8.32 |
Laval nozzle throat length (mm) | 10 | 1.67 |
Laval nozzle divergent length (mm) | 90 | 15 |
Laval nozzle number | 4 | 4 |
Bottom tuyere number | 6 | 6 |
Liquid phase density (kg·m−3) | 7100 | 1000 |
Top blowing gas density (kg·m−3) | 1.43 | 1.29 |
Bottom blowing gas density (kg·m−3) | 1.62 | 1.29 |
Oxygen lance height (mm) | 1350 | 120 |
Top gas flow rate (m3·h−1) | 22,000 | 73 |
Single bottom gas flow rate (m3·h−1) | 18, 24, 30, 42, 48, 54, 60, 66, 72, 78, 84 | 0.09, 0.12, 0.15, 0.21, 0.24, 0.27, 0.30, 0.33, 0.36, 0.39, 0.42 |
Bottom Blowing Mode | Flow Rate Per Tuyere (m3·h−1) | |||||||
---|---|---|---|---|---|---|---|---|
#1 | #2 | #3 | #4 | #5 | #6 | |||
Case 1 | Uniform mode | Uniform | 0.24 | 0.24 | 0.24 | 0.24 | 0.24 | 0.24 |
Case 2 | Continuous mode | Three-point linear co-direction | 0.12 | 0.24 | 0.36 | 0.36 | 0.24 | 0.12 |
Case 3 | Three-point linear unco-direction | 0.12 | 0.24 | 0.36 | 0.12 | 0.24 | 0.36 | |
Case 4 | Two-point linear | 0.36 | 0.36 | 0.36 | 0.12 | 0.12 | 0.12 | |
Case 5 | Circumferential linear | 0.09 | 0.15 | 0.21 | 0.27 | 0.33 | 0.39 | |
Case 6 | Interval mode | A-type | 0.15 | 0.42 | 0.15 | 0.15 | 0.42 | 0.15 |
Case 7 | V-type | 0.30 | 0.12 | 0.30 | 0.30 | 0.12 | 0.30 | |
Case 8 | Triangle alternating | 0.12 | 0.36 | 0.12 | 0.36 | 0.12 | 0.36 |
Items | Case 1 | Case 2 | Case 3 | Case 4 | Case 5 | Case 6 | Case 7 | Case 8 |
---|---|---|---|---|---|---|---|---|
Dead zone (%) | 11.63 | 7.42 | 10.19 | 12.79 | 9.08 | 7.96 | 14.88 | 12.19 |
Weak flow zone (%) | 46.87 | 52.37 | 49.37 | 49.97 | 49.95 | 52.74 | 48.78 | 50.37 |
Active flow zone (%) | 41.49 | 40.22 | 40.44 | 37.25 | 40.97 | 39.30 | 36.34 | 37.44 |
Average velocity (m·s−1) | 0.04758 | 0.05013 | 0.04799 | 0.04673 | 0.04828 | 0.04937 | 0.04583 | 0.04709 |
Average turbulent kinetic energy (m2·s−2) | 0.00152 | 0.00171 | 0.00158 | 0.00147 | 0.00161 | 0.00164 | 0.00146 | 0.00149 |
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Sun, J.; Zhang, J.; Lin, W.; Feng, X.; Liu, Q. Effect of Bottom Blowing Mode on Fluid Flow and Mixing Behavior in Converter. Metals 2022, 12, 117. https://doi.org/10.3390/met12010117
Sun J, Zhang J, Lin W, Feng X, Liu Q. Effect of Bottom Blowing Mode on Fluid Flow and Mixing Behavior in Converter. Metals. 2022; 12(1):117. https://doi.org/10.3390/met12010117
Chicago/Turabian StyleSun, Jiankun, Jiangshan Zhang, Wenhui Lin, Xiaoming Feng, and Qing Liu. 2022. "Effect of Bottom Blowing Mode on Fluid Flow and Mixing Behavior in Converter" Metals 12, no. 1: 117. https://doi.org/10.3390/met12010117