结晶器喂钢带连铸坯凝固过程的数学模拟

利用旅行薄片微元体能量守恒原理,引入喂钢带相对速度参量,发展了连铸凝固旅行薄片数学模型.采用有限体积法,用Visual Basic语言独立编制源码模拟程序,并对一典型喂钢带的连铸工艺进行模拟分析,得到了连铸坯温度分布和喂进钢带凝固状态的曲线.结果证明,喂进钢带改变了结晶器内温度场的分布和传统的由表及里凝固方式,钢带在结晶器内先凝固后熔化,降低了钢水过热度和铸坯断面温度梯度,使得温度分布更有利于等轴晶结晶过程的进行,有利于铸坯断面形核率的提高.同时该模型也给出了钢带尺寸、拉速和过热度等参数对连铸坯凝固过程的影响.

Mathematical Model on Steel Strip--Feeding of Mold in Continuous Casting Process

A mathematical model for feeding strip steel process has been developed using energy conservation principle on traveling thin-cell and introduction of relative steel strip feeding speed. Model equations are solved by using the finite volume method, and computer code is made out by Visual Basic language. The numerical simulation is carried out on a typical feeding steel strip in continuous casting mold. The temperature distribution of continuous casting strand and solidification state curve of feeding strip steel are obtained. The results show that conventional temperature field and solidification behavior from surface to interior of strand are changed by a feeding strip steel process. Strip steel in mold firstly solidifies and then melts again, the superheat of molten steel and temperature gradient of strand decrease. These are beneficial for formation of equiaxed dendrite in strand. At the same time, the effects of some parameters such as size of feeding strip steel, casting speed and superheat on solidification process are also studied.