共查询到18条相似文献,搜索用时 171 毫秒
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冷却壁安全工作是保证高炉长寿的基础。通过设计并建造冷却壁热态实验炉,研究了高炉铸铁冷却壁热面无渣皮和有渣皮时的非稳态传热过程,考察了不同炉气温度条件下冷却壁热电偶温度的变化规律。回归得到了炉气在升温阶段、稳定阶段、降温阶段时冷却壁热电偶温度随时间的变化关系式。计算得出了冷却壁热面在有无渣皮条件下的平均热流强度,回归得出了炉气平均对流换热系数随炉温的变化关系。结果表明,冷却壁热面在有渣皮时热电偶温度的变化速率显著低于无渣皮时的变化速率,冷却壁破损的主要原因是冷却壁温度的反复变化和渣皮的频繁脱落而产生的热应力。 相似文献
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高炉炉墙热负荷的传热学分析和研究 总被引:10,自引:1,他引:9
应用传热学理论计算了冷却器设计参数,炉衬厚度,渣铁凝固层厚度以及对流换热系数对炉墙热负荷的影响。结果表明:高炉炉墙的热负荷与冷却水管直径,冷却水管间距和镶砖的导热系数成正比,与冷却水管距冷却壁热面的距离,镶砖厚度和面积成反林;改变冷却壁的设计参数虽然使炉墙的热负荷增大,但炉墙的热面工作温度却反而降低。这有利于保护炉衬。 相似文献
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炉缸冷却壁冷却性能主要体现在冷却水与水管间的对流传热。因为工程上常用计算对流换热系数的经验公式不能满足不同的水流状态从而导致炉缸热应力分析误差较大,所以以某高炉炉缸结构为例,首先利用传热学准数方程推导出冷却水处于不同流动状态时对应的综合对流换热系数表达式,同时探讨了对流换热系数经验公式的适用范围;然后通过迭代计算推导出了冷却水处于层流状态下考虑衰减热阻时的综合对流换热系数表达式;最后对烘炉状态下炉缸侧壁传热模型进行瞬态传热与冷却分析,得到了微水烘炉甚至闭水烘炉的热工依据,可为初步制定高炉烘炉制度进行评估和完善。 相似文献
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高炉铸铜冷却壁热面状况计算模型的开发与实践 总被引:1,自引:0,他引:1
根据铸铜冷却壁的结构特点,分析了铸铜冷却壁的传热过程,重点研究了冷却壁本体与冷却水之间的传热热阻,提出了高炉铸铜冷却壁热面状况计算模型。通过采集和处理现场高炉数据,以及采用编程技术实现了该模型的在线计算,并且成功应用到了国内某钢铁公司高炉生产中。实践证明,该模型可以有效地帮助工长实时把握冷却壁热面状况,加强对炉型的管理,当发生渣皮厚度异常时,可以提早进行操作干预,有效避免了渣皮大面积脱落或者结厚,从而对于高炉顺行和高炉长寿等起到了促进作用。 相似文献
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XIE Ning-Qiang Shu-Sen Cheng 《钢铁研究学报(英文版)》2010,17(1):1-1
In order to study the effect of gas temperature variation on cooling stave,temperature,stress and displacement distributions of cooling stave were analyzed respectively when gas temperature inside blast furnace increases from 1000 to 1600℃.The results show that the temperature field on cold side is under control of cooling pipes and hardly changes when gas temperature increases.The temperature gradient and change rate with time near hot sides are greater than those in other regions and the later can reach 100℃/s.The stress intensity near middle area of hot surface is up to 400MPa and that's why there are lots of cracks at this place.The edge of stave is bent to cold side and middle regions between fixed bolts and pin moves to hot side.The displacement around fixed pin is smaller but larger on the edge and the maximum is located on hot side of top surface.The maximum displacement in z direction is about 4mm and 3mm in y direction.If the expansion coefficient of packing layer is 1/4,the thickness of packing layer between the cooling staves is 32mm and 24mm between sides up and down. 相似文献
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提高高炉炉腰及炉身下部冷却壁抗热变形能力是维持高炉长寿的关键.采用热态实验和数值模拟手段研究高炉炉腰及炉身下部区域铜钢复合冷却壁的传热及热变形行为,并与铜冷却壁进行对比分析.铜钢复合冷却壁热面无渣铁壳覆盖,煤气温度1200℃条件下,铜钢复合冷却壁最高温度为180℃,传热性能与铜冷却壁接近.铜钢界面最大等效应力约为114.45 MPa,低于铜钢复合板的抗拉强度.铜钢复合冷却壁发生弯曲变形,中心z向位移为0.66 mm,较铜冷却壁低约25.8%;顶底端沿z向位移为0.13 mm,较铜冷却壁低约50%;曲率为0.93×10-4 mm-1,较铜冷却壁低约51.81%.铜钢复合冷却壁抗变形能力优于铜冷却壁,可以避免铜冷却壁热变形过大导致的螺栓及冷却水管断裂破损问题. 相似文献
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WANG Chao WANG Zhao-dong YUAN Guo WANG Dao-yuan WU Jun-ping WANG Guo-dong 《钢铁研究学报(英文版)》2013,20(5):1-05
For plate quenching on a roller quenching machine, heat transfer process is investigated. According to the practical online experiment of plate center temperature, average heat transfer coefficient under different conditions and temperature fields are analyzed by numerical simulation. The results show that, at the water temperature of 15 ℃, the instantaneous maximum quenching cooling rate is 17.6 ℃/s for the plate of 50 mm in thickness in roller quenching process. In the temperature range of 400-850 ℃, the maximum is 12.1 ℃/s. With the plate surface temperature decreasing, surface heat transfer coefficient increases at first, and reaches the maximum value of about 15 000 W/(m~2·K), and then decreases. The calculated heat transfer coefficients are applied to analyze plate temperature field of different thicknesses, and the difference between the calculated and measured temperature is less than 5%. 相似文献
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小模块冷却壁是将性能优异的耐火材料直接浇铸在平行排列的冷却水管上而形成的一种新型冷却设备。采用ANSYS软件建立了小模块冷却壁温度场计算模型,利用该模型计算了炉气温度为1200~1600℃、冷却水流速为0.5~2.5m/s条件下壁体材质导热系数、水管材质、水管直径、水管间距、冷却水流速及工作环境温度等条件变化时小模块冷却壁的温度分布状况。结果表明,小模块冷却壁对炉气温度变化的适应能力较强,壁体材质导热系数、水管间距、壁体厚度对小模块冷却壁传热性能影响较大,而水管直径、水管材质及水流速的影响较小。 相似文献
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GONG Dian-yao XU Jian-zhong PENG Liang-gui WANG Guo-dong LIU Xiang-hua 《钢铁研究学报(英文版)》2007,14(4):11-14
The mathematical model for online controlling hot rolled steel cooling on run-out table (ROT for abbreviation) was analyzed, and water cooling is found to be the main cooling mode for hot rolled steel. The calculation of the drop in strip temperature by both water cooling and air cooling is summed up to obtain the change of heat transfer coefficient. It is found that the learning coefficient of heat transfer coefficient is the kernel coefficient of coiler temperature control (CTC) model tuning. To decrease the deviation between the calculated steel temperature and the measured one at coiler entrance, a laminar cooling control self-learning strategy is used. Using the data acquired in the field, the results of the self-learning model used in the field were analyzed. The analyzed results show that the self-learning function is effective. 相似文献
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不同工况下铸铁冷却壁热负荷分析 总被引:1,自引:0,他引:1
采用有限元软件ANSYS建立高炉冷却壁稳态传热模型,利用ANSYS单元生死技术模拟冷却壁表面渣皮熔化行为,以计算铸铁冷却壁在渣皮稳定、渣皮脱落、冷却壁烧损和冷却壁烧毁4种工况下的温度分布和热负荷。分析结果表明,冷却壁热负荷随着炉气温度的升高而增加,提高冷却水速度和壁体烧损变薄对热负荷的影响较小。渣皮脱落和冷却壁完全消失造成热负荷急剧增加。 相似文献