【作者】 刘晶晶；

【导师】 白明华；

【作者基本信息】 燕山大学 ， 机械设计及理论， 2012， 硕士

【摘要】 随着现代工业的发展，现有普通尺寸规格的方坯难以满足市场的需求，如在桥梁、隧道建造行业，亟需一些大断面尺寸的钢材来满足其基础建设的需要。本文根据实际需要提出建设700mm×700mm特大方坯，并依据大方坯连铸的特点，分析了结晶器传热过程及新型结晶器技术的特点，针对700mm×700mm特大方坯提出了在结晶器内部设置内冷却器的方案。运用CFD技术及ANSYS对复合冷却结晶器内钢水的流场、温度场、钢水的凝固传热行为及结晶器壁的温度场与应力进行了仿真分析，其为以后700mm×700mm特大方坯的建设及新型结晶器技术的深入研究提供了理论指导。(1)给出了复合冷却结晶器的结构简图，理论分析了设置内冷却器的作用。(2)利用FLUENT软件，建立了复合冷却结晶器内部铸坯的三维模型，对采用不同结晶器浇注时结晶器内部流场与温度场进行了研究。通过对比分析结果，得到了采用复合冷却结晶器的优点。(3)运用FLUENT软件中凝固/熔化模型，研究了复合冷却结晶器内钢水的凝固行为。给出了结晶器内不同截面处的温度云图与液相分数云图，绘制了铸坯内部及表面的温度曲线、铸坯坯壳厚度的生长曲线。(4)建立了外结晶器、内冷却器与钢水流固耦合传热数学模型，对结晶器壁与钢水间的传热热阻进行了深入研究，考虑了气隙热阻及结晶器内钢水流场对结晶器温度场的影响，计算得到了外结晶器、内冷却器的温度场分布；运用ANSYS结合计算所得到的温度场计算了外结晶器、内冷却器的热应力分布，这为以后深入研究内冷却器在连铸结晶器中的应用提供了依据。更多还原

【Abstract】 With the development of modern industry, the traditional dimension steel can hardlymeet the needs of market, such as bridge and tunnel industry, thus supercolossalcross-section slab is greatly needed to satisfy the infrastructural needs. This papersuggested building700mm×700mm supercolossal bloom continuous casting machine onthe basis of practical needs. The process of heat transfer of mold and the characteristicsof new mold technology were analyzed according to bloom continuous casting. Finally,an inner cooler was applied to the mold of700mm×700mm bloom. CFD technology andANSYS software were used to do simulation of the flow, temperature and solidificationprocess of molten steel in the mold, and the temperature and thermal stress of mold wereanalyzed as well. It has theoretical and practical significance in the built of700mm×700mm bloom continuous casting, doing further research about new moldtechnology.(1) The drawing of the complex mold was given and analyzed the effects of innercooler.(2) The CFD software FLUENT was applied to build the3-D model of slab ofcomplex mold, the flow and the temperature of mold were studied when different moldswere used to casting. The advantages of complex were vividly revealed according toresult of simulation.(3) The processes of solidification of molten steel were in-depth studied with the useof solidification/molten model of FLUENT. The temperature contour and liquid fractioncontour of the different cross-section of mold, the temperature curve of slab and surfacecentral, the curve of shell thickness along mold were given.(4) Fluid-Solid interaction coupling thermal model of outer mold and inner coolerwith steel were built, which was used to study the temperature distribution of outer moldand inner cooler. The heat resistance was closely investigated, the influence of the heatresistance between steel and mold and the flow of mold were considered in the process of modeling. ANSYS software was applied to calculate the stress and strain distribution oftwo parts of complex mold combined with temperature, which provided reference forfurther research in continuous casting and inner cooler.更多还原