共查询到19条相似文献,搜索用时 109 毫秒
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连铸板坯凝固传热模型研究及应用 总被引:1,自引:0,他引:1
依据板坯连铸机工艺条件,利用铸坯凝固过程传热数学模型计算了铸坯凝固过程温度场分布和坯壳生长情况,并探讨连铸工艺因素对铸坯温度和凝固过程的影响,示例性的提出了提高铸坯温度的工艺手段。 相似文献
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钢厂1#连铸机以0.95 m/min拉速生产SS400,D36和X70钢150~180 mm连铸板坯时,易产生角部纵裂纹,发生率最高可达5%。利用商业有限元软件ANSYS,建立了板坯连铸结晶器二维切片式凝固传热数学模型,并采用传热和应力/应变直接耦合的方法对连铸过程结晶器内凝固传热进行计算,分析了各钢种在0.95~1.05m/min拉速下铸坯温度分布以及温度分布不均引起的热应力。工业试验结果表明,根据优化计算结果,将板坯结晶器窄面的锥度系数由原来的1.00%改进为1.10%后,有效地消除了1#连铸机板坯的角部纵裂纹。 相似文献
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热送热装工艺中板坯连铸过程传热的数学模型 总被引:2,自引:0,他引:2
建立了板坯连铸过程传热数学模型,并用实测数据对计算结果进行了验证,证明该模型可用于预报不同操作条件下板坯凝固过程中温度的变化和凝固状态。应用该模型分析了影响板坯出连铸机温度的主要因素:板坯尺寸、拉速、二冷水量及冷却方式等。适当提高拉速、改善二冷制度能提高铸坯出连铸机温度。 相似文献
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针对板坯连铸铸坯常出现角部横裂纹缺陷,建立了板坯连铸结晶器与铸坯二维瞬态热力耦合有限元模型,研究了板坯结晶器窄面铜板在不同倒角结构和不同锥度情况下铸坯的凝固收缩行为,计算了铸坯在结晶器内的温度和应力分布情况。模型较全面地考虑了保护渣和气隙对传热的影响。数值模拟结果表明:结晶器窄面铜板倒角过大或过小,都不利于铸坯温度的均匀分布;对断面厚度为230mm的铸坯,窄面铜板采用20mm~25mm ×45°;倒角及抛物线锥度时,铸坯表面温度分布最均匀,最大平面主应力分布较合理,角部出现横裂纹的可能性会大大降低。 相似文献
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宝钢1930mm板坯连铸凝固传热模型的研究与开发 总被引:1,自引:0,他引:1
以二维非稳态传热数学模型为理论基础,结合铸坯在连铸二冷区的实际热量散失规律,将二冷区相邻夹辊之间传热分为夹辊接触传热、水聚集蒸发传热、水冲击传热和辐射传热四个过程,并根据宝钢一炼钢板坯连铸机具体条件,建立了宝钢1930mm板坯连铸凝固传热模型.利用面向对象的VB6.0高级语言对模型进行编程,开发出相应的连铸二冷仿真软件.利用红外线测温仪采集铸坯温度,对模型结果进行验证,现场铸坯测温和仿真结果比较得出偏差范围为0.9%~2.8%,说明仿真模型和仿真结果真实可靠.利用该仿真软件可以对宝钢1930mm连铸机的二冷工艺制度进行研究和优化,指导连铸生产. 相似文献
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《钢铁冶炼》2013,40(7):552-560
AbstractA software to simulate the solidification, heat transfer and water flowrate distribution in slab continuous casting was developed by establishing a mathematical model for the heat transfer and solidification in medium thickness slab casting. This model was validated by pin shooting and surface temperature measurement experiments. A reasonable target surface control temperature was found by testing the high temperature mechanical properties of Nb bearing ship plate steel, and then the water flowrate of each loop of the secondary cooling zone was determined by the software. The influence of uneven secondary cooling in the slab width direction on the quality of the slab was also investigated, which provided data for the optimisation of the secondary cooling of the slab caster. On the basis of the above research, an optimisation scheme for a secondary cooling system was proposed. Experimental results showed that the quality of the slab was significantly improved after optimisation. The centreline macrosegregation was reduced, and the ratio of equiaxed grains was increased by 3·18%. In addition, the transverse cracking of the slab was almost eliminated. 相似文献
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《钢铁冶炼》2013,40(7):546-551
AbstractA mathematical model based on an inverse heat transfer calculation was built to determine the heat flux between the mould and slab based on the measured mould temperatures. With K–? turbulence model, a mathematical model of three-dimensional heat transfer and solidification of molten steel in continuous slab casting mould is developed. Solidification has been taken into consideration, and flow in the mushy zone is modelled according to Darcy’s law as is the case of flow in the porous media. The heat flux prescribed on the boundaries is obtained in the inverse heat conduction calculation; thus, the effect of heat transfer in the mould has been taken into consideration. Results show that the calculated values of mould temperature coincide with the measured ones. Results also reveal that the temperature distribution and shell thickness are affected by the fluid flow and heat transfer of slab which is governed by the heat flux on the mould/slab interface. 相似文献
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薄板坯连铸结晶器铜板温度及热流密度分布 总被引:5,自引:1,他引:4
薄板坯连铸结晶器的传热过程直接影响到铜板的寿命,有必要研究薄板坯连铸结晶器的传热特征。为了研究薄板坯结晶器的热流密度,通过开发的结晶器温度监测软件检测了珠钢结晶器铜板的温度。根据在线实测的铜板温度以及薄板坯连铸机冷却参数,建立了薄板坯结晶器铜板传热模型,计算并验证了结晶器热流密度的分布函数,同时通过二次回归得出了结晶器热流密度与结晶器高度的关系式。结果表明,在宽度方向上铜板温度和热流密度的分布具有相似的规律性,距离弯月面越近,热流密度和温度的波动越大。弯月面处热流密度值大于4.2MW/m^2,是造成结晶器铜板被侵蚀的主要原因。 相似文献
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A three-dimensional heat transfer model considering various skid button heights for the prediction of the temperature history of steel slabs was performed in order to obtain the optimal heating pattern of these slabs with minimum energy consumption in a walking-beam type reheating furnace. An algorithm was developed using a simplified conjugated-gradient method combined with a shooting method and was used as an optimiser to design the furnace temperature distribution. The effect of the skid button heights on the design requirements, such as the energy consumption necessary for heating a slab, skid-mark temperature uniformity at the furnace exit and slab discharging temperature, was investigated. The parametric study results indicated that the skid-mark temperatures significantly decrease with increases in the skid button heights. In addition, the optimal designs suggested lower energy consumption for heating a slab and improved skid-mark temperature uniformity as compared to the original operating conditions in a steel plant. 相似文献
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