scholarly journals Optimization of Flow Field in Slab Continuous Casting Mold with Medium Width Using High Temperature Measurement and Numerical Simulation for Automobile Exposed Panel Production

Metals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 9
Author(s):  
Peng Jiang ◽  
Jian Yang ◽  
Tao Zhang ◽  
Gangjun Xu ◽  
Hongjun Liu ◽  
...  
Keyword(s):  
Flow Field ◽  
Flow Pattern ◽  
Gas Flow ◽  
Mold Surface ◽  
Level Fluctuation ◽  
Gas Flow Rate ◽  
Continuous Casting Mold ◽  
Argon Gas ◽  
Surface Level ◽  
Slab Continuous Casting

In the present work, mathematical modeling combined with measurement of the velocities near mold surface with rod deflecting method at the high temperature was carried out to optimize the flow field of slab continuous casting mold with medium width of 1230 mm for the production of an automobile exposed panel. The results show that the measured results of the velocities near the mold surface are in good agreement with the calculated results. The velocities near the mold surface increase with increasing the casting speed and decreasing the argon gas flow rate. When the casting speed is increased from 1.0, to 1.3, 1.5, and 2.0 m/min, the flow pattern in the mold is changed from single-roll flow (SRF), to unstable flow (UF), and then to double-roll flow (DRF), the top surface level fluctuations has the smallest value at 1.5 m/min. When the argon gas flow rate is 1 and 4 L/min, the velocity near the mold surface has a moderate value, and the flow pattern in the mold is DRF and the top surface level fluctuation is small and symmetrical. When the submerged entry nozzle (SEN) submergence depth is increased to 200 mm, the velocities near the mold surface decrease, and the top surface level fluctuation becomes small. The optimized flow field in the mold can be judged to be favorable to the surface quality of the automobile exposed panel; if the velocities near the mold surface are relatively small, the flow pattern in the mold is DRF and the top surface level fluctuation is small and symmetrical.

scholarly journals Flow Field in Slab Continuous Casting Mold with Large Width Optimized with High Temperature Quantitative Measurement and Numerical Calculation

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 261
Author(s):  
Chao Ma ◽  
Wen-yuan He ◽  
Huan-shan Qiao ◽  
Chang-liang Zhao ◽  
Yi-bo Liu ◽  
...  
Keyword(s):  
Flow Field ◽  
Flow Pattern ◽  
Flow Rate ◽  
Casting Speed ◽  
Gas Flow ◽  
Immersion Depth ◽  
Mold Surface ◽  
Gas Flow Rate ◽  
Argon Gas ◽  
Slag Entrainment

In this paper, the rod deflection method was applied to quantitatively measure velocity near the mold surface at high temperatures and the k-ε model coupled with a discrete phase model (DPM) was adopted to simulate the flow field in the mold. The calculated results match very well with the measured results under all the present conditions. Under the conditions of the large mold width of 1800 mm, 1.1 m/min casting speed and 140 mm submerged entry nozzle (SEN) immersion depth, the velocity near the mold surface decreases with increasing the argon gas flow rate. When the argon gas flow rate is 6 L/min, the flow pattern is the double roll flow (DRF). When the argon gas flow rate is increased to 10 L/min and 14 L/min, the flow pattern is the single roll flow (SRF), and the risk of slag entrainment increases. With an argon gas flow rate of 10 L/min, and an immersion depth of 160 mm, the velocity near the mold surface sensitively increases with increasing the casting speed. When the casting speed is 1.1 m/min, an intermediate flow (IF) is formed with the intensified mold surface fluctuation, which can easily result in slag entrainment defects. When the casting speed is only increased to 1.2 m/min, the velocity near the mold surface changes drastically and is close to the upper limit velocity of 0.4 m/s. When the casting speed is 1.1 m/min, and the argon gas flow rate is 10 L/min, the velocity near the mold surface is obviously increased with increasing the immersion depth. When the immersion depth of the nozzle increases from 140 mm and 160 mm to 180 mm, the flow pattern changes from SRF or IF to DRF. When the bottom shape of the SEN changes from mountain to well, the velocity near the mold surface decreases. We suggest adopting the well-bottom nozzle to reduce the risk of slag entrainment.

scholarly journals Comparison of the Flow Field in a Slab Continuous Casting Mold between the Thicknesses of 180 mm and 250 mm by High Temperature Quantitative Measurement and Numerical Simulation

Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1886
Author(s):  
Yibo Liu ◽  
Jian Yang ◽  
Fuxiang Huang ◽  
Keran Zhu ◽  
Fenggang Liu ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
High Temperature ◽  
Flow Field ◽  
Continuous Casting ◽  
Quantitative Measurement ◽  
Powder Layer ◽  
Mold Surface ◽  
Continuous Casting Mold ◽  
Casting Mold ◽  
Slab Continuous Casting

In the present work, the flow field in a slab continuous casting mold with thicknesses of 180 and 250 mm are compared using high temperature quantitative measurement and numerical simulation. The results of the numerical simulation are in agreement with those of the high temperature quantitative measurement, which verifies the accuracy and reliability of the numerical simulation. Under the same working conditions, the velocities near the mold surface with the thickness of 180 mm were slightly higher than those of the mold with the thickness of 250 mm. The flow pattern in the 180 mm thick mold maintains DRF more easily than that in 250 mm thick mold. The kinetic energy of the jet dissipates faster in the 250 mm thick mold than in the 180 mm mold. For double-roll flow (DRF), as the argon gas bubbles can be flushed into the deeper region under the influence of strong jets on both sides, the argon bubbles distribute widely in the mold. For single-roll flow (SRF), as the argon bubbles float up quickly after leaving the side holes, the bubble distribution is more concentrated in the width direction, which may cause violent interface fluctuation and slag entrainment. The fluctuation at the steel-slag interface in the mold with 180 mm thickness is greater than that in the mold with 250 mm thickness but less than 5 mm. The increase of mold thickness may lead to a decrease of the symmetry of the flow field in the thickness direction and uniformity of mold powder layer thickness. In summary, the steel throughput should be increased in the 250 mm thick mold compared with that in the 180 mm thick mold.

scholarly journals Effect of Mold Width on the Flow Field in a Slab Continuous-Casting Mold with High-Temperature Velocity Measurement and Numerical Simulation

Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1943
Author(s):  
Jian-Qiu Liu ◽  
Jian Yang ◽  
Chao Ma ◽  
Yi Guo ◽  
Wen-Yuan He ◽  
...  
Keyword(s):  
Kinetic Energy ◽  
Flow Field ◽  
Flow Velocity ◽  
Turbulent Kinetic Energy ◽  
Flow Rate ◽  
Gas Flow ◽  
Immersion Depth ◽  
Gas Flow Rate ◽  
Argon Gas ◽  
Slag Entrainment

In this paper, the effects of the width of the mold on the surface velocity, flow field pattern, turbulent kinetic energy distribution, and surface-level fluctuation in the mold were studied with measurement of the flow velocity near the surface of the mold at high temperature with the rod deflection method and numerical calculation with the standard k-ε model coupled with the discrete-phase model (DPM) model for automobile exposed panel production. Under the conditions of low fixed steel throughput of 2.2 ton/min, a nozzle immersion depth of 140 mm, and an argon gas flow rate of 4 L/min, as the width of the mold increases from 880 mm to 1050 mm and 1300 mm, the flow velocity near the surface of the mold decreases. The flow direction changes from the positive velocity with the mold widths of 880 mm and 1050 mm to the unstable velocity with the mold width of 1300 mm. The calculated results are in good agreement with the measured results. The turbulent kinetic energy near the submerged entry nozzle (SEN) gradually increases, and the risk of slag entrainment increases. Under the conditions of high fixed steel throughput of 3.5 ton/min, the SEN immersion depth of 160 mm, and the argon gas flow rate of 10 L/min, as the width of the mold increases from 1600 mm to 1800 mm and 2000 mm, the velocity near the mold surface decreases. The flow velocity at 1/4 of the surface of the mold is positive with the mold width of 1600 mm, while the velocities are negative with the widths of 1800 mm and 2000 mm. The calculated results are basically consistent with the measured results. The high turbulent kinetic energy area near the nozzle expands to a narrow wall, and the risk of slag entrainment is significantly increased. In both cases of low and high fixed steel throughput, the change rules of the flow field in the mold with the width are basically the same. The argon gas flow rate and the immersion depth of SEN should be adjusted reasonably to optimize the flow field in the mold with different widths under the same fixed steel throughput in the practical production.

scholarly journals Numerical simulation of the oxygen distribution in silicon melt for different argon gas flow rates during Czochralski silicon crystal growth process

2018 ◽  
Vol 204 ◽  
pp. 05013
Author(s):  
Zumrotul Ida ◽  
Jyh-Chen Chen ◽  
Thi Hoai Thu Nguyen
Keyword(s):  
Flow Pattern ◽  
Oxygen Concentration ◽  
Flow Rate ◽  
Growth Process ◽  
Gas Flow ◽  
Silicon Crystal ◽  
Gas Flow Rate ◽  
Flow Rates ◽  
Argon Gas ◽  
Flow Motion

The effects of argon gas flow rate on the oxygen concentration in Czochralski (CZ) grown silicon crystal were examined. To analyze the influence of the argon gas flow rate in CZ growth process, a 200 mm length silicon single crystal was grown. Different argon gas flow rates are considered. The melt flow pattern, temperature and oxygen concentration distributions in the melt and crystal-melt interface are calculated. The results show that the transport of oxygen impurity is quite dependent on the flow motion in the melt. As the argon gas flow rate increases, there is no fundamental change in flow motion of the melt and the oxygen concentration decreases to a minimum value. When the argon gas flow rate increases further, the flow pattern under the melt-crystal interface starting changes and the oxygen concentration has increased after. Therefore, there is an optimum value for the argon gas flow rate for obtaining the lowest oxygen concentration in the melt.

scholarly journals Influence of M-EMS on Fluid Flow and Initial Solidification in Slab Continuous Casting

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3681
Author(s):  
Guoliang Liu ◽  
Haibiao Lu ◽  
Bin Li ◽  
Chenxi Ji ◽  
Jiangshan Zhang ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flow Field ◽  
Continuous Casting ◽  
Casting Speed ◽  
Liquid Pool ◽  
Industrial Test ◽  
Magnetic Flux Density ◽  
Continuous Casting Mold ◽  
Slab Continuous Casting ◽  
Initial Solidification

A mathematical model coupled with electromagnetic field has been developed to simulate the transient turbulence flow and initial solidification in a slab continuous casting mold under different electromagnetic stirring (EMS) currents and casting speeds. Through comparing the magnetic flux density, flow field with measured results, the reliability of the mathematical model is proved. The uniform index of solidified shell thickness has been introduced to judge the uniformity of the solidified shell. The results show that a horizonal recirculation flow has been generated when EMS is applied, and either accelerated or decelerated regions of flow field are formed in the liquid pool. Large EMS current and low casting speed may cause the plug flow near the mold narrow face and a suitable EMS current can benefit to the uniform growth of solidified shell. Meanwhile, an industrial test exhibits that EMS can weaken the level fluctuation and number density of inclusion. Overall, a rational EMS current range is gained, when the casting speed is 1.2 m/min, the rational EMS current is 500–600 A.

Effects of U-Shape Inner Cooler on Flow and Solidification of Molten Steel in Slab Continuous Casting Mold

2011 ◽  
Vol 291-294 ◽  
pp. 423-427
Author(s):  
Yan Juan Jin ◽  
Xiao Chao Cui ◽  
Zhu Zhang
Keyword(s):  
Fluid Dynamics ◽  
Temperature Field ◽  
Flow Field ◽  
Continuous Casting ◽  
Molten Steel ◽  
Continuous Casting Mold ◽  
Slab Continuous Casting ◽  
Cooling Technology ◽  
Steel Flow

An inner-outer coupled cooling technology of molten steel for 1240×200mm slab continuous casting, that is to set an inner cooler—U shape pipes in the mold, is put forward in order to enhance the efficiency of transmitting heat and improve inner structure of billet. The flow status and solidification status of molten steel under coupling flow field and temperature field in inner-outer coupled cooling mold are simulated by using fluid dynamics software, and compare with those in traditional mold. It is found that setting inner cooler in the mold can make molten steel flow status even, which is favorable to floating up of the inclusion, quickening the solidification of steel liquid and improving the quality of billet.

scholarly journals The gas flow pattern through small size Resistive Plate Chambers with 2 mm gap

2021 ◽  
Vol 16 (11) ◽  
pp. P11022
Author(s):  
Y. Pezeshkian ◽  
A. Kiyoumarsioskouei ◽  
M. Ahmadpouri ◽  
G. Ghorbani
Keyword(s):  
Gas Flow ◽  
Fluid Dynamic ◽  
Gas Flow Rate ◽  
Argon Gas ◽  
Dynamic Methods ◽  
Gas System ◽  
Gas Molecules ◽  
Simulation Results ◽  
Resistive Plate Chambers ◽  
The Difference

Abstract A prototype of a single-gap glass Resistive Plate Chamber (RPC) is constructed by the authors. To find the requirements for better operation of the detector's gas system, we have simulated the flow of the Argon gas through the detector by using computational fluid dynamic methods. Simulations show that the pressure inside the chamber linearly depends on the gas flow rate and the chamber's output hose length. The simulation results were compatible with experiments. We have found that the pressure-driven speed of the gas molecules is two orders of magnitude larger in the inlet and outlet regions than the blocked corners of a 14 × 14 cm2 chamber, and most likely the difference in speed is higher for larger detectors and different geometries.

Sign in / Sign up

Export Citation Format

Share Document