共查询到19条相似文献,搜索用时 437 毫秒
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攀钢板坯连铸二冷喷嘴性能的热态实验研究 总被引:2,自引:0,他引:2
基于钢坯的非稳态导热原理,采用金属试样单侧加热至二冷段金属表面温度再进行冷却的实验方法,模拟水/气-水喷嘴性能对钢坯冷却过程的影响.按攀钢板坯连铸的二冷段喷嘴布置方式和主要生产铸坯的品种规格,设计喷嘴特性与单、双喷嘴条件下铸坯强制冷却传热过程研究的实验方案.通过对喷嘴传热性能的测试,得到了水/气-水喷嘴在不同喷水压力下的传热系数;实验得到的双喷嘴平均传热系数与生产过程数据计算的传热系数的误差在5%~9%以内,研究结果表明喷嘴传热性能的热态实验可以为合理布置喷嘴、优化二冷制度提供依据. 相似文献
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针对板坯表面裂纹和内部裂纹两大类质量缺陷,基于凝固传热仿真、应力应变计算及连铸相关冶金工艺理论分析,并结合浇铸异常事件专家知识库方法,开发了CISDI板坯质量在线诊断分析数学模型及其应用软件CISDI_SQDS ONLINE R2011,其中引入裂纹生成指数来作为质量评级的参考理论指标,并在其计算过程中耦合考虑了与浇铸冶金准则密切相关的质量损失因子和异常事件对应的调节因子,实现了理论解析与专家系统的有机结合,为板坯质量的预测和控制提供了重要的理论工具,以期在板坯连铸生产中得以有效的推广应用。 相似文献
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板坯宽度是粗轧带钢产品最重要的质量指标之一,其直接影响到带钢成品的尺寸精度。要确保生产的粗轧板坯宽度尺寸精度达到要求,就必须加强对粗轧板坯宽度控制系统的研究。文中分析了板坯宽度模型、板坯宽度影响因素,提出了模型自适应板坯宽度控制系统。 相似文献
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The thermal efficiency of a reheating furnace was predicted by considering radiative heat transfer to the slabs and the furnace wall. The entire furnace was divided into fourteen sub-zones, and each sub-zone was assumed to be homogeneous in temperature distribution with one medium temperature and wall temperature, which were computed on the basis of the overall heat balance for all of the sub-zones. The thermal energy inflow, thermal energy outflow, heat generation by fuel combustion, heat loss by the skid system, and heat loss by radiation through the boundary of each sub-zone were considered to give the two temperatures of each sub-zone. The radiative heat transfer was solved by the FVM radiation method, and a blocked-off procedure was applied to the treatment of the slabs. The temperature field of a slab was calculated by solving the transient heat conduction equation with the boundary condition of impinging radiation heat flux from the hot combustion gas and furnace wall. Additionally, the slab heating characteristics and thermal behavior of the furnace were analyzed for various fuel feed conditions. 相似文献
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Ibrahim Dincer 《国际能源研究杂志》1995,19(3):227-233
The present study deals with the experimental and theoretical analysis of the transient heat transfer from an individual slab body to the medium during freezing. In this respect, a new model was developed to determine the heat transfer coefficient and this heat transfer coefficient was used in the computation of the dimensionless theoretical temperature distribution. On the other hand, experimental work was performed to measure the centre temperatures of the individual slab products (viz. dried figs) during freezing at the median temperature of -22°C. In the comparison of the theoretical and experimental temperature distributions, very good agreement was found. 相似文献
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针对钢铁企业的氧化烧损问题,用数值模拟的方法进行预测分析。利用CFD流体计算软件建立了炉内流动、燃烧、辐射、钢坯导热和氧化烧损模型,流动模型采用k—ε湍流模型,燃烧采用PDF燃烧模型,辐射换热模型采用离散坐标(DO)辐射模型,热流密度做为钢坯导热的边界条件,模拟钢坯在实际工况下的结果表明,氧化铁皮的快速增长期是在钢坯入炉50~120min之间,位于加热段;在不同均热时间下,钢坯氧化率随均热时间呈线性增长。据此结论,现场操作人员可通过强化加热段加热能力的手段减少钢坯在加热段的停留时间或热装钢坯调整总的在炉时间来降低钢坯氧化烧损率以提高钢坯加热质量。 相似文献
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《International Journal of Heat and Mass Transfer》2007,50(19-20):3740-3748
A mathematical heat transfer model for the prediction of heat flux on the slab surface and temperature distribution in the slab has been developed by considering the thermal radiation in the furnace chamber and transient heat conduction governing equations in the slab, respectively. The furnace is modeled as radiating medium with spatially varying temperature and constant absorption coefficient. The steel slabs are moved on the next fixed beam by the walking beam after being heated up through the non-firing, charging, preheating, heating, and soaking zones in the furnace. Radiative heat flux calculated from the radiative heat exchange within the furnace modeled using the FVM by considering the effect of furnace wall, slab, and combustion gases is introduced as the boundary condition of the transient conduction equation of the slab. Heat transfer characteristics and temperature behavior of the slab is investigated by changing such parameters as absorption coefficient and emissivity of the slab. Comparison with the experimental work show that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace. 相似文献
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This work is concerned with the investigation of the thermoelastic response of a composite slab (a two-, thin-, metallic-layered plate) under the effect of an intense rapid heating applied to one side. The dual-phase-lag heat conduction model is used to derive the heat equation in each layer. The heat equations are solved using the Laplace transform technique and the Riemann-sum method. As a result, the thermal behavior, in the form of the temperature distribution along the thickness direction of the slab, is determined. The governing equation of plate deflection is formulated and solved for simply supported edge conditions. As a result, the plate deflections and the thermal stresses are calculated numerically using the finite difference method. Thermal stress distribution is found to depend on the temperature distribution in addition to the difference in the thermal and mechanical properties of the materials that compose the two layers. 相似文献
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The paper presents an entropy generation analysis for steady conduction in a slab with temperature‐dependent volumetric internal heat generation. The slab experiences asymmetric convective cooling on its two faces. The exact analytical solution for the temperature distribution is used to compute dimensionless local and total entropy generation rates in the slab. The total entropy generation rate depends on five dimensionless parameters: reference heat generation temperature Q, the heat generation–temperature variation parameter a, the temperature asymmetry parameter λ, and Biot numbers Bi1 and Bi2. Graphs illustrating the effect of these five parameters on the local and total entropy generation rates are presented and discussed. It is found that the total entropy generation in the slab can be minimized with a suitable choice of the cooling parameters. The paper corrects the flawed entropy results published recently. The present results for the special case of uniform internal heat generation confirm the results presented in a 2003 paper. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20404 相似文献