Numerical Simulation of Bubble and Velocity Distribution in a Furnace
Abstract
:1. Introduction
2. Model Theory
2.1. Water Model Experiment
2.2. CFD-VOF Model
2.2.1. Volume of Fluid Model (VOF)
2.2.2. Turbulence Model (RNG k-ε Model)
2.3. Geometric Model and Boundary Conditions
3. Results and Discussion
3.1. Model Verification
3.2. Distribution of Bubbles
3.3. Velocity Distribution
3.4. Average Turbulent Kinetic Energy
4. Conclusions
- Comparing the behavior of bubble motion, the simulation results were similar to the experimental results. This shows the accuracy of the simulation parameters selected in the simulation calculation and confirms the feasibility of establishing a mathematical model for numerical simulation.
- As the inlet velocity increased, the bubbles concentrated towards the middle, and the liquid level fluctuation became more intense. The depth of chlorine entering the molten salt with an inlet velocity of 60 m/s was about four times the depth with an inlet velocity of 15 m/s. In terms of velocity distribution, excessive or too small an inlet velocity may lead to the uneven distribution of chlorine in molten salt. Therefore, an inlet velocity of about 30 m/s is more appropriate. To find a more accurate inlet velocity, further research is needed.
- With the increase in liquid density, the number of bubbles was almost the same, the fluctuation range of liquid level was relatively small, and the velocity distribution was very similar. Therefore, changing the liquid density had little effect on the bubble and velocity distribution.
- Although the increase in liquid viscosity increased the gas holdup, it resulted in the poor fluidity of bubbles in the molten salt. In order to ensure that the gas holdup and fluidity of chlorine in molten salt are proper, it is necessary to select the appropriate liquid viscosity to facilitate the subsequent chemical reaction.
- The average turbulent kinetic energy and its fluctuation amplitude increased with the increase in inlet velocity. This shows that increasing the inlet velocity is beneficial to enhancing the stirring effect. After reaching a dynamic balance, the average turbulent kinetic energy under different liquid densities and viscosities was roughly the same while the value of average turbulent kinetic energy under different liquid densities was 0.51 m2/s2 and under different viscosities was 0.55 m2/s2.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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Parameters | Liquid/Gas | Density/kg/m3 | Viscosity/Pa·s |
---|---|---|---|
Prototype | Molten salt | 1650 | 0.0055 |
Chlorine | 2.9 | 1.4473 × 10−5 | |
Model | Water | 1000 | 1.01 × 10−3 |
Air | 1.29 | 1.79 × 10−5 |
No. | Inlet Velocity/(m/s) | Liquid Density/(kg/m3) | Liquid Viscosity/(Pa·s) |
---|---|---|---|
1 | 15 | 1650 | 0.0055 |
2 | 30 | ||
3 | 60 | ||
4 | 30 | 1261 | |
5 | 1650 | ||
6 | 1650 | 0.0100 | |
7 | 0.0500 |
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Ding, W.; Qi, B.; Chen, H.; Li, Y.; Xiong, Y.; Saxén, H.; Yu, Y. Numerical Simulation of Bubble and Velocity Distribution in a Furnace. Metals 2022, 12, 844. https://doi.org/10.3390/met12050844
Ding W, Qi B, Chen H, Li Y, Xiong Y, Saxén H, Yu Y. Numerical Simulation of Bubble and Velocity Distribution in a Furnace. Metals. 2022; 12(5):844. https://doi.org/10.3390/met12050844
Chicago/Turabian StyleDing, Weitian, Bing Qi, Huiting Chen, Ying Li, Yuandong Xiong, Henrik Saxén, and Yaowei Yu. 2022. "Numerical Simulation of Bubble and Velocity Distribution in a Furnace" Metals 12, no. 5: 844. https://doi.org/10.3390/met12050844