Hongwei PAN
,
Shusen CHENG
金属学报(英文版)
doi:10.1016/S1006-7191(08)60102-7
In this paper, the subject of mathematical model is a series of math expressions, which is used to calculate different regions' volume fraction and analyze flow characterization in multi-strand tundish. But research about mathematical model for multi-strand tundish is few, and so far, there has been no acknowledged math model for multi-strand tundish to describe its flow characteristic. If Sahai's model, which is originally proposed for the case of single-strand tundish (proposed in reference[10], and this model is widely used in the world), is applied to describe flow feature in multi-strand tundish, the calculation results would be unreasonable. Based on the data of water-model experiment results, the sum of each strand's dead region's volume fraction is bigger than 100 %, and this obviously doesn't agree with reality; and the value of dead region's volume fraction is calculated to be minus according to mathematical simulation results data in another case. What's more, Sahai's model does not propose the standard of plotting the RTD-curve, and this makes scholars around the world can't achieve consensus of views about plotting RTD-curve. And the model doesn't consider the bypass flow and can't calculate its volume fraction, but bypass flow is critical to tundish metallurgy. And through Sahai's model, the calculation result of plug flow region's volume fraction is also not reasonable, because the model doesn't well describe the essence of plug flow. So these suggest that it is not reliable to apply Sahai's single-strand tundish model to multi-strand tundish case. Then a new model is attempted to propose in this paper for your discussion. In the new model, the standard of plotting RTD curve is definitely proposed, and relative calculation method is also proposed; and the feature of dead region is carefully studied and the model proposes a new method to calculate its volume fraction, and the calculation formula about its volume fraction can be adjustable according the actual demand; what's more, the new model considers the bypass flow and proposes a method to calculate its volume fraction for the first time, and then volume fraction of plug flow region, backmix flow region, dead region and bypass flow can be calculated and obtained at the same time; and this new model can better capture the deviation of reality flow pattern from ideal plug flow pattern, and reflects the feature of plug flow.
关键词:
Tundish
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null
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null
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null
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null
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null
冯士超
,
王艳红
,
丁瑞锋
上海金属
概述了电磁技术的作用及特点,介绍国外钢铁企业在电磁设备的设计及成本控制方面的研究成果,重点叙述新日铁、JFE、浦项和ABB公司电磁搅拌技术的最新研究进展,以及新日铁脉冲电磁技术和塔塔钢铁公司中间包电磁控流技术的发展.简要说明了国内科研院所和钢铁企业通过对电磁设备的使用参数进行优化设置,改善铸坯中心偏析和疏松等缺陷.指出未来国内钢企应加强电磁设备的自主研发和设计,保证设备良好的冶金效果,并提高设备使用灵活性以及降低操作和维护成本.
关键词:
连铸
,
结晶器
,
中间包
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电磁技术
张娜
,
张明军
,
李凤善
,
陈伟庆
上海金属
为了降低钢中夹杂物数量,根据相似原理进行小方坯六流非对称中间包的水模拟研究.通过模拟分析原型中间包流场,找出其存在的问题,提出通过在原中间包中合适位置加设挡墙、挡坝、开设导流孔等的方法来优化中间包结构,共设计了包括六流浇注和五流浇注在内的5种优化方案.优化结果为:六流浇注优化后比原型中间包的停留时间增加105.2％,死区比例减小60.4％.五流浇注优化后比原型中间包的停留时间增加172％,死区比例减小76％.优化后各流之间差异性明显减小.
关键词:
连铸
,
六流非对称
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中间包
,
结构优化
,
水模型
