共查询到20条相似文献,搜索用时 15 毫秒
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Liangcai Zhong Liying Li Bao Wang Maofang Jiang Lixing Zhu Li Zhang Rongrong Chen 《国际钢铁研究》2006,77(2):103-106
Fluid flow characteristics in a two‐strand slab tundish with Ar bubbling curtain were studied in water modelling experiments. It was found that the Ar bubbling curtain can greatly improve the flow characteristics in the tundish with a weir, a dam and a turbulence inhibitor. It dramatically increased the peak concentration time and plug volume and greatly decreased the dead volume, but hardly influenced the minimum residence time. Therefore, the fluid flow characteristics in a tundish with Ar bubbling curtain were favourable to the flotation and separation of inclusions from molten steel. The flow characteristics with low gas flow rate and short distance of the Ar bubbling curtain from the tundish outlet were better than those with high gas flow rate and large distance of the curtain from the outlet. 相似文献
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《钢铁研究学报(英文版)》2011,(Z2):256-262
This paper presents experimental results from physical and mathematical simulation of liquid steel flow in the tundish adopting gas bubbling curtain substituting dam and industrial trials have been investigated based the experimental results. Physical and mathematical simulation results show the gas bubbling curtain can improve pattern of liquid flow in the tundish , accelerate inclusions flotation,and simultaneity metallurgy effect has been further improved when combining weir and turbulence inhibitor. The industrial trial results confirm that content of oxygen , nitrogen and inclusions in continuous casting billets have been reduced when gas bubbling curtain combining weir and turbulence inhibitor. 相似文献
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Inertial and buoyancy driven water flows under gas bubbling and thermal stratification conditions in a tundish model 总被引:5,自引:0,他引:5
A. Vargas-Zamora J. Palafox-Ramos R. D. Morales M. Díaz-Cruz J. de J. Barreto-Sandoval 《Metallurgical and Materials Transactions B》2004,35(2):247-257
Steel flow dominated by inertial and buoyancy flows under gas bubbling and thermal stratification conditions, in a one-strand
tundish, was studied using a 2/5 scale water model. The use of a turbulence inhibitor yields plug flow volume fractions well
above 40 pct for a casting rate of 3.12 tons/min under isothermal conditions. Small flow rates of gas injection (246 cm3/min), through a gas curtain, improved the fluid flow by enhancing the plug flow volume fraction. Higher flow rates originated
an increase of back-mixing flow, thus forming recirculating flows in both sides of this curtain. Step inputs of hot water
drove streams of this fluid toward the bath surface due to buoyancy forces. A rise in gas flow rate led to a thermal homogenization
in two separated cells of flow located at each side of the gas curtain. Step inputs of cold water drove streams of fluid along
the tundish bottom. Use of the gas curtain homogenized the lower part of the tundish as well as the upper part of the bath
at the left side of the curtain. However, temperature at the top corner of the tundish, in the outlet box, remained very different
than the rest of the temperatures inside this tundish. High gas flow rates (912 cm3/min) were required to homogenize the bath after times as long as twice the mean residence time of the fluid. Particle image
velocimetry (PIV) measurements corroborated the formation of recirculating flows at both sides of the gas curtain. 相似文献
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在相似理论的基础上,通过水力学模拟对两流板坯连铸中间包3种不同挡墙挡坝组合形式下包内流场进行研究.试验结果表明:方案1(挡墙-挡坝-端挡坝方案)挡墙与挡坝间距不合理,端挡坝未起到控流作用致使中间包内流体平均停留时间、峰值时间短,死区比例较大(27.9%);方案2(挡坝-挡墙-端挡坝方案)显著改善了中间包内流场状况,全混流区及活塞流区比例增加,死区减小为21%;方案3(双墙双坝方案)由于增加一组挡墙延长了流体流动的路径,流体在中间包内的停留时间明显增加,死区比例最小(16.7%),同时微观电导率波动值也最小(0.025 ms/cm),为3种方案之最优. 相似文献
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Hydraulics and Mathematics Simulation on the Weir and Gas Curtain in Tundish of Ultrathick Slab Continuous Casting 总被引:1,自引:0,他引:1
Dengfu Chen Xin Xie Mujun Long Min Zhang Leilei Zhang Qi Liao 《Metallurgical and Materials Transactions B》2014,45(2):392-398
The molten steel flow pattern in continuous casting tundish could be improved if the flow control devices were properly used. With reasonable application of weir and air curtain, the disturbance at injection zone of the tundish was reduced. The flow path of the molten steel was changed, and the short-circuit flow was eliminated. Therefore, the residence time was lengthened. An air curtain with bubbles floating could promote the surface flow and improve inclusions removal. The application of weir and air curtain in an ultrathick slab continuous casting tundish was investigated with hydraulics and mathematics simulation. The residence time and dead volume fraction were studied through orthogonal experiments with different positions of the flow control devices. The efficiency of three factors was analyzed, and the optimum positions of the weir and air curtain were obtained. Besides, the discrete phase model was suitable for simulation of the interaction between gas bubbles and molten steel, and the mathematics results shown the optimum one got larger inclusion flotation rate. 相似文献
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中间包结构优化及冶金效果 总被引:2,自引:2,他引:0
通过水模型实验,对四流圆坯中间包三种挡墙形式下的包内流场进行模拟研究.结果表明:原挡墙控流下的中间包同一侧两流之间的流体流动特性存在很大差异,与内侧相比,外侧流的最小停留时间、峰值时间长、死区体积大,造成中间包内钢液温度不均匀,夹杂物不能有效地上浮去除.U型挡墙能很好地解决各流间的同步性,但是最小停留时间短,死区比例较大.采用Y型挡墙可以有效地改变中间包内流场分布,促进夹杂物上浮,提高钢水清洁度,为三种挡墙形式之最优.工业试验表明,Y型挡墙在降低铸坯总氧和夹杂物方面均优于原挡墙. 相似文献
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In the present work, the behaviour of a gas bubbling curtain (GBC) in the continuous casting tundish of industry is studied by using a physical model in the scale of 1:3. This study was made with the following configurations of gas injection inside the tundish: no gas injection, gas injection on the bottom and combined gas injection (CGI) on the bottom and the walls. Mathematical simulations were performed using the Eulerian approach. Mathematical modelling was also used to determine the residence time distribution curves (RTD curves). For the validation of the mathematical model, experiments were made using the physical models to obtain the homogenisation time of salt solutions. All of the results were validated by the experimental results of the RTD curves. The plug flow fraction remained almost constant when gas injection was used on the walls, however the mean residence time and the dead volume fraction, increased and decreased, respectively. The CGI on the bottom and walls allowed the entire cross-section to be covered with the GBC which acted as a barrier to the passage of inclusions. 相似文献
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薄板坯连铸中间包内抑湍器的模拟研究 总被引:3,自引:0,他引:3
控制中间包内钢液的合理流动对夹杂物的排除有重要影响,为此建立了模拟薄板坯连铸中间包流动情况的水模型。通过测定停留时间分布(RTD)曲线,研究了不同组合控流装置对中间包流体流动特性的影响。结果表明,结构及尺寸合理的抑湍器能延长水口响应时间及平均停留时间、提高活塞流区体积分数及降低死区体积分数;抑湍器与单坝组合的控流装置在控制流体流动方面效果极佳,而抑湍器与单墙单坝、单墙双坝组合的控流装置的控流效果不太理想。 相似文献
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Numerical Investigation of the Fluid Flow in Continuous Casting Tundish Using Analysis of RTD Curves 总被引:2,自引:1,他引:1
A detailed mathematical procedure of the optimization of the fluid flow in a tundish water model with and without flow control devices (weir and dam) was carried out using the commercial CFD code FLUENT 60. The (k ε) two equation model was used to model turbulence. The residence time distribution (RTD) curves were used to analyze the behavior of the flow in tundish. The location of flow control devices in the tundish was studied. The results show that the flow modifiers play an important role in promoting the floatation of nonmetallic inclusions in steel. Comparing the three geometric configurations that are considered (bare tundish, weir, weir+dam), the tundish equipped with the arrangement (weir+dam) is a best and optimal geometric configuration of tundish. 相似文献
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摘要:过渡包在薄带连铸过程中起到承上启下的作用,为了使结晶器入口钢液成分与温度更加均一,研究钢液在过渡包内的流动以及其出口钢液温度的分布对薄带连铸过程有着重要的意义。针对某钢厂多流式过渡包,提出在包内增加坝堰组合以优化钢液在包内的流态以及温度分布。采用数值模拟和物理模拟的方法,研究了过渡包内不同控流装置下钢液的流态和温度分布,同时通过各流出口的平均停留时间和温度值差来考察钢液分布的均匀性。研究发现增加坝堰组合后,过渡包内流态与温度分布更加均一且稳定,过渡包内设置坝高30mm,堰高30mm,坝堰间距120mm,堰距入口中心距离253mm为最优方案,其平均停留时间方差较原模型减少82%,各出口温度极差较原模型减少67%。数值模拟结果同物理模拟结果较一致。 相似文献
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Fluid Flow and Interfacial Phenomenon of Slag and Metal in Continuous Casting Tundish With Argon Blowing 总被引:1,自引:0,他引:1
The fluid flow and the interfacial phenomenon of slag and metal in tundish with gas blowing were studied with mathematical and physical modeling, and the effects of gas flowrate, the placement of porous beam for the generation of bubbles, and the combination of flow control devices on the flow and slag-metal interface were investigated. The results show that the position of gas bubbling has a significant effect on the flow in tundish, and the placement of porous beam and gas flowrate are the two main factors affecting the entrapment of slag in tundish. The closer the porous beam to the weir, the more reasonable is the flow, which is in favor of the control of slag entrapment in tundish. 相似文献
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