共查询到20条相似文献,搜索用时 0 毫秒
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This study aims to propose suitable simulation methods, which enable to reduce the major differences between water model and real caster, such as the gradually decreased flow space, flow mass in the casting direction, and the momentum decay in the mushy zone. With consideration of solidified process, the method is concerned with the change of flow space and flow mass at the casting direction in water model. The level fluctuations, stimulus–response curves, velocities of liquid surface, and distributions of liquid slag have been changed in the water model to study the differences of flow character and the variation of fluid flow in molds. The mold with a solidified shell leads to significant differences in flow behaviors, such as higher level fluctuations, higher surface velocities, and worse liquid slag distributions. Neglecting the solidified shell causes unrealistic lower surface velocities and level fluctuations in water model. The mold with consideration of flow mass balance has higher level fluctuations and surface velocities than the mold without shell, and has lower level fluctuations and surface velocities than that of mold with a shell. The results indicate that it is necessary for water model to take the solidified process into account to acquire more accurate and reliable experiment results, especially for thinner slab. 相似文献
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Effects of Electromagnetic Brake,Mold Curvature and Slide Gate on Fluid Flow of Steel in a Slab Mold
The influence of mold curvature, slide gate and magnetic forces on the steel flow in a slab mold was studied with a 3‐D mathematical model. The slide gate application induces a biased flow toward the mold side where its opening is located in the submerged entry nozzle (SEN). Turbulence and asymmetry of flows are more intense in a curved mold than in a straight mold. The effect of an electromagnetic brake (EMBr), located in the discharging ports to control flow turbulence, is only appreciable when magnetic flux density is higher than 0.1 T. The magnetic flux density does not affect the velocity profile in the discharging ports in the SEN because its construction material is insulated. Increasing the magnetic flux density leads to a decrease of the discharging jets angle and to the elimination of the two upper roll flows. The use of the EMBr in a curved mold equipped with a slide gate eliminates the meniscus velocity spikes observed in the mold corners. These results help to demonstrate that EMBr eliminates the asymmetry in a curved mold even under the excessive turbulent conditions existing in curved continuous casting molds. 相似文献
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对大方坯连铸结晶器电磁搅拌过程的流场和温度场进行了数值模拟,并讨论了搅拌强度对流场和温度场的影响。结果表明:在结晶器电磁搅拌下,搅拌器区域的钢液变为水平旋转,使从水口向下吐出的钢水与向上回流的钢水流股相冲突,流股侵入深度变浅,从而使轴向温度迅速降低,径向温度升高,提高了热区位置,有利于传热;搅拌强度越大,钢水的二次流现象越明显,热区位置越高。 相似文献
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ZHU Miao-yong WANG Jun ZHANG Ying 《钢铁研究学报(英文版)》2005,12(6):14-19
SymbolList Ab,An———Surfaceareaofbroadfaceandnarrowfaceof moldrespectively,m2;Cp———Effectiveheatcapacity,J·kg-1·K-1;Cp,s———Heatcapacityofsolidphase,J·kg-1·K-1;Cp,l———Heatcapacityofliquidphase,J·kg-1·K-1;Cw———Waterheatcapacity,J·kg-1· 相似文献
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Flow of Steel in Mold Region During Continuous Casting 总被引:1,自引:0,他引:1
The particle image velocimetry (PIV) technique was used to study the fluid flow phenomena that occurred during continuous casting, using a water model with dimensions of 1 840 mm×280 mm. Two types of solidified shells, ie, the smooth type and the coarse type, were used to characterize the dendrite in order to simulate different liquid solid interfacial conditions. The influence of the nozzle angle and the immersion depth of nozzle, as well as the casting speed on the flow behavior was investigated quantitatively. The results were as follows: (1) There are two large recirculations above and below the fluid jet in the mold, respectively, under the smooth interface condition. However, in the case of the dendrite solidified shell, it was found that the flow velocity of the fluid decreased and more smaller vortices appeared in the upper region of the mold. (2) The angle and the immersion depth of nozzle are two important factors affecting the flow pattern, and they are also capable of bringing about the change in the flow direction. (3) The higher the casting speed, the higher are the jet stream and the impacting point on the narrow face. However, the high casting speed causes serious fluctuation of the meniscus, and correspondingly leads to various defects. 相似文献
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Thequalityofsteelbiletiscloselyrelatedtotheflowfieldinmold.Whenmoltensteelwithnon-metalicinclusionispouredintomold,steeljetus... 相似文献
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以鞍山钢铁集团公司中薄板坯连铸机为研究对象,利用商业软件CFX44对结晶器内钢水流场和传热凝固进行了数值模拟,主要研究了三孔浸入式水口的冶金特征及其对结晶器内钢水流场和温度场的影响。结果表明,采用三孔浸入式水口可以优化结晶器内钢水流场和温度场,稳定坯壳发育和成形,防止拉漏。 相似文献
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连铸结晶器电磁搅拌对夹杂物的影响 总被引:6,自引:0,他引:6
在连铸过程中 ,夹杂物对钢的质量有着重要影响。本文分析了结晶器电磁搅拌对夹杂物的作用机理 ,简要叙述了结晶器电磁搅拌对铸坯内夹杂物含量、大小、分布及其形态的影响 相似文献
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电磁场对改善钢材质量的作用 总被引:7,自引:3,他引:4
研究了电磁制动技术对结晶器内钢液流动及夹杂物迁移行为的作用,以及电磁搅拌和电磁超声波对钢材料凝固组织的影响。研究结果表明,在恒稳电磁场作用下,钢液内形成的与钢液流动相反的电磁力可有效地控制钢液流动、稳定液面波动,有利于夹杂物的去除;在电磁搅拌和电磁超声波的作用下,金属的凝固组织得到细化,等轴晶比率明显提高。计算了磁场对奥氏体/铁素体及铁素体/奥氏体平衡边界的影响,磁场对相图的奥氏体/铁素体界限产生很大影响,使其向高成分或高温度区域移动;随成分不同,磁场每增加1T,钢的Ae3温度升高2~3℃。研究了电场奥氏体化对中碳合金钢40MnMoV性能的影响,与常规工艺处理样品相比,电场奥氏体化可使其硬度值升高,且冲击性能和拉伸性能的指标都有所提高。 相似文献