高拉速板坯结晶器浸入式水口的优化

针对1400 mm×180 mm断面、最高拉速为1.6 m/min的结晶器,应用相似原理,建立了水模型,研究浸入式水口对结晶器内流场的影响。结果表明：当拉速为1.6 m/min时,侧孔20 mm×30 mm,下倾角度21°,开底孔13 mm的水口比较合适。     

水口参数对异形坯连铸结晶器内流场的影响

依据湍动能理论，本建立了结晶器内钢液的三维湍流模型，开发了计算程序，研究了不同水口状态下异形坯结晶器中钢水的流动特性。利用本模型所得计算结果与实测结果吻合较好，并可对现场生产进行离线分析。     

舞阳钢铁公司板坯连铸机结晶器的流场和温度场研究

舞阳钢铁公司开发特宽特厚板，与包头钢铁学院合作研究不同工艺条件下结晶器内的流场温度场，这些工艺因素包括坯尺寸，拉坯速度，水口插入深度，水口倾角，水口面积，过热度等，得出了一些对漏钢及结果状态有意义的结论。     

Zr-C质浸入式水口侵蚀机理的研究

针对Zr-C质浸入式水口易侵蚀现象,选取某钢厂被侵蚀的Zr-C质水口试样,采用扫描电镜对试样的侵蚀物进行检测,并在实验室进行验证,研究Zr-C质浸入式水口的侵蚀机理。结果表明:现场Zr-C质浸入式水口的侵蚀机理是机械冲刷和化学侵蚀,以SiO2和CaO为主要成分的结晶器保护渣对Zr-C质浸入式水口的侵蚀作用较大,且有新的化合物生成,产物为Ca0.15Zr0.85O1.85。     

连铸浸入式水口(SEN)的发展

随着连铸技术的发展,连铸用功能耐火材料之一的浸入式水口也取得了很大的发展。介绍浸入式水口的作用和结构及其材质的发展。     

板坯连铸机结晶器内钢液流场的数值模拟

基于流体力学的基本理论,利用商业软件fluent的,κ-ε湍流模型,实现了对结晶器内钢液流场的三维数学模拟.重点分析了浸入式水口的形状、插入深度、水口侧孔倾角以及拉速等工艺参数对结晶器钢液流场的影响.结果表明,对于断面为1280 mm × 180 mm的板坯结晶器,水口插入深度为150 mm,水口倾角为向下15°,拉坯速度为1 m/min时,结晶器内的流场较好.     

浸入式水口结构与工艺参数配合优化的物理模拟

以鞍钢二炼钢厂小方坯连铸机为原型进行浸入式水口(SEN)结构参数、连铸操作工艺参数配合优化的物理模拟实验,得到了适合鞍钢二炼钢厂生产需要的SEN结构参数和操作工艺参数,在此基础上分析了SEN的结构参数与操作工艺参数对结晶器内钢液流动状况的影响.     

特殊钢方坯连铸结晶器内的速度场及水口形式的研究

针对特殊钢方坯连铸结晶器,四孔水口向上15°的浇注工艺,采用相似理论进行了模型设计.观察并用二维激光多普勒测速仪[LDA]测定了两工况条件下结晶器内的流场及相应的出口速度,得出了流场特点和出口射流特性.本文的研究结果,为实际生产中合理的水口形式,夹杂物的去除提供了定量依据,是进一步研究结晶器内的传热模型,夹杂物的分离模型,铸坯的凝固特性的前提和基础.     

ZCGS浸入式水口材料与钢中Al2O3反应性能的研究

通过对ZCGS（ZrO2-CaO-C－SiO2)材料进行热力学分析，选用了以ZCGS材料为内壁与Al2O3-C基体制成复合浸入式水口，经现场工业试验表明，对要求钢中酸溶铝较高的优势低合金16MnReL钢进行浇铸时，该复合浸入式水口具有良好的抗Al2O3沉积效果，能够满足铝镇静钢及优质低合金钢多炉连铸的要求。     

宝钢板坯连铸机中间包三维流场数模研究

本文根据宝钢板坯连铸机中间包的形状和操作工艺参数,建立了一个钢液流动的三维数学模型,并利用数值计算结果,分析了宝钢中间包上、下挡墙结构对钢液流场的影响。结果表明,这种结构的中间包,有较合理的钢液流场。可避免钢渣卷入钢液流向水口进入结晶器,也有利于钢液内的夹杂上浮排除。     

Characteristics of shell thickness in a slab continuous casting mold

The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold.A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid (VOF) model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions.The results show that the jet acts a stronger impingement on the shell of narrow face,which causes a zero-increase of shell thickness in a certain range near the impingement point.The thinnest shell on the slab cross-section locates primarily in the center of the narrow face,and secondly near the comer of the wide face.Nozzle optimization can obviously increase the shell thickness and make it more uniform.     

Heat-transfer model on the improvement of continuous casting slab temperature

A heat transfer model on the solidification process has been established on the basis of the technical conditions of the slab caster in No.3 steel works of Wuhan Iron & Steel Corporation, and the temperature field in the solidifying slab was calculated which was verified by the measured slab surface temperature. The influences of the main operating factors including casting speed, spray cooling patterns, superheat of melt and slab size on the solidification process were analyzed and the means of enhancing the slab temperature was brought forward. Raising the casting speed to 1.3 m/min, controlling the flowrate of secondary cooling water and improving the cooling pattern at the lower segments of secondary cooling zone could improve the slab temperature effectively. And the increasing the superheat is adverse to the production of high temperature slab.     

Influence of submerged entry nozzle clogging on the behavior of molten steel in continuously cast slab molds

The influence of submerged entry nozzle clogging on the behavior of molten steel in continuously cast slab molds was studied using commercial code CFX4.3. The results indicate that clogging at the top part of the nozzle port not only increases the velocity of molten steel, but also enhances the wall shear stress, F number and heat flux. This clogging has the greatest effect on the behavior of molten steel. However, clogging at the top 1/3 of the nozzle only increases the velocity of molten steel and has little influence. Clogging at the bottom of the nozzle almost has no influence.     

小方坯高速连铸时结晶器应力场有限元模拟

利用六面体八节点单元，建立结晶器的三维应力模型，利用小方坯结晶器温度场的计算结果，模拟了不同结晶器铜板厚度和不同冷却水流速下结晶器的应力．结果表明，结晶器壁越薄，变形越严重。应力越大；冷却水流速对结晶器应力的影响不大．同时表明。合适的结晶器厚度为10mm，合适的冷却水流速为9—12m／s．     

Water modeling of mold powder entrapment in slab continuous casting mold

The optimal parameters were determined by the water modeling of slab casting. It was found that there are mainly three types of mold powder entrapment in slab continuous casting, i.e., the entrapment caused by the shearing flow near the narrow face of mold, the entrapment caused by vortexes around the submerged entry nozzle (SEN), and the entrapment caused by the Ar bubbling. Both the velocity of the surface flow and the level fluctuation of the liquids are enlarged with increasing the casting speed, reducing the submersion depth of SEN, decreasing the downward angles of the nozzle outlets, and increasing the Ar flowrate, all of which in- crease the tendency of mold powder entrapment. Among the four above-mentioned factors, casting speed has the largest effect.     

Mathematical model of heat transfer for bloom continuous casting

A mathematical model for heat transfer during solidification in continuous casting of automobile steel, was established on researching under the influence of the solidifying process of bloom quality of CCM in the EAF steelmaking shop, at Shijiazhuang Iron and Steel Co. Ltd. Several steel grades were chosen to research, such as, 40Cr and 42CrMo. According to the results of the high temperature mechanical property tests of blooms, the respective temperature curves for controlling the solidification of different steels were acquired, and a simulating software was developed. The model was verified using two methods, which were bloom pinshooting and surface strand temperature measuring experiments. The model provided references for research on the solidifying process and optimization of a secondary cooling system for automobile steel. Moreover, it was already applied to real production. The calculated temperature distribution and solidification trend of blooms had offered a reliable theory for optimizing the solidifying process of blooms, increasing withdrawal speed, and improving bloom quality. Meanwhile, a new secondary cooling system was designed to optimize a secondary cooling water distribution, including choice and arrangements of nozzles, calculation of cooling water quantity, and so on. 2008 University of Science and Technology Beijing. All rights reserved.     

Numerical simulation of A1203 deposition at a nozzle during continuous casting

The effects of various factors,such as argon flow rate and slide gate opening ratio,on the alumina deposition rate were re- searched by the numerical simulation method.The pressure in the nozzle is significantly affected by argon flow rate and slide gate opening ratio.To keep positive pressure in the nozzle,the argon flow rate should be increased with a decrease in slide gate opening ratio.The effect of argon flow rate on the alumina deposition rate depends on the condition of opening ratio or casting speed.The ef- fect of increasing the argon flow rate on the deposition rate is not obvious when the opening ratio is small.The Al_2O_3 deposition rate decreases significantly with an increase in argon flow rate when the argon flow rate is low,but it decreases slowly when the argon flow rate reaches a certain value.The alumina deposition rate is linear with alumina content at different slide gate opening ratios and argon flow rates.The observed thickness of the deposition layer at the bottom and outlet of a real clogged nozzle is almost equal to the result of the numerical simulation.     

板坯连铸结晶器内液面波动的水模型研究

以某厂板坯连铸结晶器为原型,采用1∶1的水模型进行实验,研究了不同工艺条件下工艺参数的变化对大板坯结晶器内流场表面波动的影响情况,提出了优化结晶器流场的工艺参数,为在实际生产中减少结晶器内卷渣提供了依据.     

Numerical simulation of Al2O3 deposition at a nozzle during continuous casting

The effects of various factors, such as argon flow rate and slide gate opening ratio, on the alumina deposition rate were researched by the numerical simulation method. The pressure in the nozzle is significantly affected by argon flow rate and slide gate opening ratio. To keep positive pressure in the nozzle, the argon flow rate should be increased with a decrease in slide gate opening ratio. The effect of argon flow rate on the alumina deposition rate depends on the condition of opening ratio or casting speed. The effect of increasing the argon flow rate on the deposition rate is not obvious when the opening ratio is small. The Al2O3 deposition rate decreases significantly with an increase in argon flow rate when the argon flow rate is low, but it decreases slowly when the argon flow rate reaches a certain value. The alumina deposition rate is linear with alumina content at different slide gate opening ratios and argon flow rates. The observed thickness of the deposition layer at the bottom and outlet of a real clogged nozzle is almost equal to the result of the numerical simulation.