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设计喷枪置于铁水包后部(相对于扒渣嘴),在扒渣开始前,通过此喷枪向铁水内喷吹气体,气体上浮后排开一定面积渣层,使表面渣向扒渣嘴方向聚集,为下一步扒渣机的操作提供便利条件,从而减少扒渣次数,提高效率,降低铁损.使用1:3.5比例设计铁水包水模型,模拟不同工况下,气体排渣的效果.同时采用数值模拟的方法验证水模实验结果.实验表明喷枪浸入深度从200mm变到400mm,无渣比(无渣区域占总面积的百分比)从10%增加到30%;气体流量从4m3·h-1变到6m3·h-1,无渣比从30%增加到37%.说明浸入深度越大,吹气量越大,排渣的效果越好.数值模拟与水模型符合较好. 相似文献
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Hydrodynamic modeling of some gas injection procedures in ladle metallurgy operations 总被引:2,自引:0,他引:2
Experimental studies of flows generated in a 0.30 scale water model of a 150 ton steelmaking ladle are reported. These were
used to test the adequacy of a generalized two-dimensional computational scheme for predicting flows generated by fully submerged
and partially submerged gas injection lances. The roles of turbulence models and grid configuration were assessed. Predictions
for flow fields generated in a 150 ton steelworks ladle with and without tapered side walls, and with and without surface
baffles around the rising plume were considered. 相似文献
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K. Beskow L. Jonsson Du Sichen N. N. Viswanathan 《Metallurgical and Materials Transactions B》2001,32(2):319-328
In the present work, the deoxidation of liquid steel with aluminum wire injection in a gas-stirred ladle was studied by mathematical
modeling using a computational fluid dynamics (CFD) approach. This was complemented by an industrial trial study conducted
at Uddeholm Tooling AB (Hagfors, Sweden). The results of the industrial trials were found to be in accordance with the results
of the model calculation. In order to study the aspect of nucleation of alumina, emphasis was given to the initial period
of deoxidation, when aluminum wire was injected into the bath. The concentration distributions of aluminum and oxygen were
calculated both by considering and not considering the chemical reaction. Both calculations revealed that the driving force
for the nucleation fo Al2O3 was very high in the region near the upper surface of the bath and close to the wire injection. The estimated nucleation
rate in the vicinity of the aluminum wire injection point was much higher than the recommended value for spontaneously homogeneous
nucleation, 103 nuclei/(cm3/s). The results of the model calculation also showed that the alumina nuclei generated at the vicinity of the wire injection
point are transported to other regions by the flow. 相似文献
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The absorption of gas through the plume eye and of an injected gas in a steelmaking ladle process was investigated, using
a physical model of CO2 absorption into a NaOH solution. The results show that the inert gas escaping through the plume eye is ineffective in protecting
the bath from the atmosphere, and placing an oil layer (simulated slag) decreases the absorption rate significantly. Increasing
the flow rate of the inert gas not only exposes more of the liquid surface to the CO2 atmosphere, but also increases the mass transfer coefficient at the surface. The overall mass transfer between an injected
CO2 gas and NaOH solution includes the mass transfer through the surface of the bath as well as the mass transfer in the bubble
dispersion zone. The difference between the mass transfer in the bubble dispersion zone and the overall mass transfer was
found to be significant for relatively low gas flow rates. The mass transfer coefficient of CO2 in the bubble dispersion zone was estimated using available information regarding the bubble size and velocity. Mass transfer
coefficient estimated for the constant bubble frequency regime shows a dependence on gas flow rate. However, if a constant
characteristic size of bubbles is assumed as an alternative approach, the mass transfer coefficient is independent of the
gas flow rate. 相似文献
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《钢铁冶炼》2013,40(6):415-426
AbstractA mathematical model based on a computational fluid dynamics technique named SOLA-SURF and the k-? two equation turbulence model, and a water model that is one-quarter the scale of an actual ladle system, have been developed in the present study to find the optimal Ca-Si injection position for the ladle secondary refining process. Based on experimental measurements and observations from the water model and simulated results of the mathematical model, which has been verified by the experimental measurements, fluid flow phenomena and corresponding diffusion of the injected Ca-Si under various design and operating conditions have been investigated. The water model experiments and simulated results from the mathematical model for actual ladle operation show that, with an injection depth of 0·8 m and argon gas flowrate of 100, 200, and 300 L min-1, the optimal position for injection is located on the tuyere-circle centre plane, opposite side to the tuyere, and 0·5-0·8R away from the circle centre. For this injection position, the mixing time is shorter and the flow pattern favours transport of the additive to the bottom of the ladle. 相似文献
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钢包在非稳态浇注过程中易形成旋涡,导致钢渣及空气的大量卷入,严重危害了钢的质量.为了更好的研究旋涡,采用ANSYS CFX软件,分别采用k-ε和RNG k-ε 2种湍流模型对钢包非稳态浇注过程中自由表面旋涡进行数值模拟,得到自由表面从表面旋转到旋涡贯通水口的演化过程,将两者的计算结果与相关文献以及Burgers涡模型进行相互对比,得到:两者计算的旋涡演化过程、旋涡产生临界高度无差别;两者的速度场与相关文献均一致,但RNG k-ε模型更真实的表现了旋涡的剪切流动;将两者的切向速度分布与Burgers涡对比,得到RNG k-ε湍流模型与理论模型更加吻合.综上:用RNG k-ε湍流模型计算自由表面旋涡更加正确合理. 相似文献
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通过二维冷态物理模型对氧气高炉炉身喷吹煤气在炉内分布进行了实验研究,分别研究了炉身煤气总量、辅助风口直径以及炉身喷吹煤气量与炉身煤气总量之比对炉身喷吹煤气在炉内分布的影响.结果表明,炉身喷吹煤气量与炉身煤气总量之比对炉身喷吹煤气在炉身分布起决定性作用,而炉身煤气总量和辅助风口直径的影响较小.同时,在炉身煤气上升过程中涡流扩散效应的影响也较小.通过对根据实验数据绘制的炉身等浓度分布图进行研究发现,炉身煤气分布主要分为两个不同的区域,一个是炉身喷吹煤气主流区,另一个是从高炉下部产生的上升煤气主流区.在炉身等浓度分布图的基础上通过回归分析的方法推导出炉身喷吹水平喷吹煤气的渗透公式.此外,辅助风口被安装在炉身下部有利于铁矿石在炉身的间接还原. 相似文献
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《钢铁冶炼》2013,40(6):431-438
AbstractA numerical method has been employed to investigate the flow field and mixing characteristic in the Rheinsahl–Heraeus (RH) degasser with side–bottom blowing. The numerical results showed that stream flows in the up snorkel, the vacuum chamber, the down snorkel and the ladle form a large rectangular circulation zone in the RH degasser with side–bottom blowing, which can enhance the circulation flow rate effectively. For an RH with side–bottom blowing, when the included angle of the line between bottom blowing location and ladle centre and the line between two snorkels is zero, the circulation flow rate increases initially with increasing dimensionless distance between the bottom blowing location and the ladle centre and then decreases, while the mixing time increases with increasing dimensionless distance. On the other hand, when the dimensionless distance is 0·2, both the circulation flow rate and the mixing time decrease with the increasing included angle initially, reach their minimum value and then increase. The optimum values for the dimensionless distance and the included angle to achieve large circulation flow rate and small mixing time are 0·2 and π/4 in the present work. 相似文献
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