旋流水口浇注结晶器内钢水流场温度场耦合数值模拟

【作者】 崔凤兰；

【导师】 崔小朝；

【作者基本信息】 太原科技大学 ， 工程力学， 2009， 硕士

【摘要】 电磁搅拌是对金属流动、传热凝固过程进行控制的一种有效手段,有着广泛的工业应用基础。电磁搅拌通过电磁感应实现能量无接触转换,将电磁能转换为钢水的旋转动能,推动钢水旋转运动,改善铸坯凝固组织及结晶状态,从而提高连铸坯质量。国内外学者对结晶器电磁搅拌进行了充分的研究,但针对浸入式水口电磁搅拌研究比较少。本文基于Maxwell电磁搅拌理论,依据麦克斯韦尔方程得到了电磁力的解析形式,通过自行编写的UDF程序,借助于流体力学分析软件Fluent,将电磁力施加到浸入式水口的钢液体上,继而研究了该电磁力搅拌对圆坯连铸结晶器内流场、温度场的影响。同时对另一种搅拌方式即x型浸入式水口进行了数值模拟,研究了在x型浸入式水口旋流浇注下结晶器内流体的速度场、温度场及凝固场的分布规律。与电磁搅拌达到的效果基本一致。不同搅拌方式下得到的耦合数值模拟的结果表明:旋流水口有利于结晶器内流体流速的充分混合,水平方向旋流的动能使得液体在垂直方向上所具有的动能减小,垂直流速较之普通水口浇注衰减加剧,并使垂直流速在整个结晶器断面上迅速趋于均匀,冲击深度降低,起到了流体制动的作用。同时,旋流出流使得铸坯内温度场分布均匀。更多还原

【Abstract】 Electromagnetic stirring which is one of the effective methods for controlling solidification of metal has a large-scale industrial application. Electromagnetic stirring improves the solidification and internal crystalline state; thereby it enhances the quality of continuous casting by means of electromagnetic induction non-converter which transforms electromagnetic power into electromagnetic force that impels the liquid metal to stir. Domestic and foreign scholars study fully on the M-EMS research, but the study on the submerged nozzle electromagnetic stirring relatively is less than other.Based on Maxwell theory of electromagnetic stirring, the analytical form of electromagnetic force is derived according to Maxwell equations. Through the procedures of the UDF and the fluid dynamics analysis software FLUENT, the electromagnetic force is applied to the submerged entry nozzle of the liquid steel. Then research is carried on that shows the effects of electromagnetic stirring on the round billet continuous casting mold of flow field and temperature field.While another numerical simulation of X-type diversion device is researched. Distribution rule of speed field, temperature field and congeal field of fluid in crystallizer taken X-type submerged nozzle using rational flow pouring is researched.The results which are showed by different styles of stirring with numerical simulation are: the swirling flow nozzle is fit for mix of flow velocity. Horizontal swirl kinetic energy makes the liquid in the vertical direction of the energy decrease. The SEN electromagnetic stirring increases the vertical speed of decay and makes the vertical speed tend to uniformity rapidly on the mold section and reduces the impact of depth. It plays a role of braking fluid. At the same time, swirling streams make the slab temperature homogenization significantly.更多还原